US3579685A

US3579685A - Mechanism for ejecting workpieces from the matrices of upsetting machines

Info

Publication number: US3579685A
Application number: US849552A
Authority: US
Inventors: Gerardus Cornelis V Meerendonk
Original assignee: Nedschroef Octrooi Maatschappij NV
Current assignee: Nedschroef Octrooi Maatschappij NV
Priority date: 1965-12-17
Filing date: 1969-07-17
Publication date: 1971-05-25
Anticipated expiration: 1988-05-25
Also published as: GB1136448A; FR1504275A; DE1577038B1; NL6516468A; ES334435A1; SE359239B

Abstract

THE DISCLOSURE IS OF AN IMPROVED MECHANISM FOR EJECTING A WORKPIECE FROM A MATRIX AFTER FORMING THEREIN AND INCLUDES A ROCKER SHAFT CARRYING AN ADJUSTABLE CAM PIVOTED THEREON ON AN AXIS PARALLEL TO THE AXIS OF THE ROCKER SHAFT, A LEVER HAVING AN EJECTING ARM AND A FOLLOWER ARM, THE LATTER ENGAGING THE CAM ON THE ROCKER SHAFT.

Description

May 25, 1971 e. c. VAN ,DE MEERENDONK MECHANISM FOR EJECTING WORKPIECES FROM THE MATRICES OF UPSETTING MACHINES Original Filed Dec. 15. 1966 4 Sheets-Sheet 1 new INVENTOR.

FIG. 2

GERARDUS CORNELIS yAN DE MEERENDONK ATTORNEYS May 25., 1971 e. c. VAN DE MEERENDONK 3,579,685 MECHANISM FOR EJECTING WORKPIECES FROM THE MATRICES OF UPSE'ITING MACHINES Original Filed D60. 15, 1966 4 ShBBtS-Shflt l INVENTOR.

GERARDUS CORNELIS VAN DE MEERENDONK ATTORNEYS M y 1971 5. c. VAN DE MEERENDONK 3,579,535

MECHANISM FOR EJECTING WORKPIEOES FROM 4 THE MATRICES OF UPSETTING MACHINES Original Filed Dec. 15, 1966 4 Sheets-Sheet 3 INVENTOR. GERARDUS CORNELIS VAN DE MEERENDONK BY 4% W, m zg zww ATTORNEYS May 25, 1971 cs. c. VAN DE MEERENDONK 3,579,685 MECHANISM FOR EJECTING WORKPIECES FROM THE MATRICES 0F UPSETTING MACHINES Original Filed Dec. 15, 1966 4 sheets sheet ,19 "fi -""1; .l

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27 27 1 s FIG.8

INVENTOR. GERARDUS coansus VAN DE MEERENDONK BY ,w'b, M M,7 ;r f%o ATTORNEYS.

United States Patent Office US. CI. -12 6 Claims ABSTRACT OF THE DISCLOSURE The disclosure is of an improved mechanism for ejecting a workpiece from a matrix after forming therein and includes a rocker shaft carrying an adjustable cam pivoted thereon on an axis parallel to the axis of the rocker shaft, a lever having an ejecting arm and a follower arm, the latter engaging the cam on the rocker shaft.

This is a continuation of Ser. No. 602,001, filed Dec. 1-5, 1966, now abandoned.

CROSS-REFERENCE TO CORRESPONDING APPLICATION This application corresponds to an application filed in the Netherlands on Dec. 17, 1965, No. 6516468, the priority of which will be claimed.

BACKGROUND OF INVENTION (1) Field of the invention The present invention relates to the art of upsetting workpieces .to form blanks for the production of screws, bolts and the like articles and more specifically to an improved mechanism for ejecting formed workpieces from the matrices or die cavities of article forming machines.

(2) Description of prior art- The prior art discloses machines of the above type which include a frame having fixed matrices, a reciprocable carriage mounted for reciprocation in the frame carrying dies cooperating with said matrices to form articles during .the reciprocation of the carriage. The matrices are adapted to receive portions of the workpieces to be upset therein, and such machines include ejector rods for ejecting workpieces from said matrices, ejecting levers actuating said rods and a rocker shaft carrying arms for operating the ejecting levers. According to one proposal the ejecting levers are provided with adjustable cam means held in place by several fixing bolts.

The manner of locating and adjusting these cam devices on the ejecting levers is complicated and time consuming. Furthermore, the arms on the rocker shaft are fixed and operate in a rigid manner on the ejecting levers so that difficulty is encountered in maintaining the ejecting mechanism.

The problems presented by this known construction, typically illustrated in US. Pat. No. 3,171,144 (Cl. 10- 76) are overcome by the improvements provided by the present invention in that a simple cam structure is pivotally mounted on the rocker shaft, the camming surface of which is engaged by a simple follower arm of the ejecting lever. The rocker shaft, cams and follower arms are located in readily accessible positions, and the cams are provided with a simple adjusting means. In an advantageous construction the cams are located in grooves in the rocker shaft and pivoted on a pin extending transversely through the walls of the grooves parallel to the axis of the rocker shaft. This construction coupled with 3,579,685 Patented May 25, 1971 associated mechanisms described hereinafter provides a simple and effective, readily accessible ejecting mechanism.

SUMMARY OF THE INVENTION The machine disclosed in the present application is of the type used for upsetting workpieces in the production of screw, bolt and the like blanks, including a frame having fixed matrices arranged therein, a reciprocable carriage carrying dies adapted to cooperate respectively with said matrices during the reciprocation of the carriage. In this machine the matrices are adapted to receive portions of the workpieces to be upset therein, and the disclosure is more particularly directed to a mechanism for ejecting the workpieces from the matrices after they have been worked on in the machine.

More specifically the disclosure is directed to an ejecting mechanism including ejector rods, ejecting levers and a rocker shaft carrying adjustable cams for respectively cooperating with said levers for actuating the ejector rods.

Each lever is pivotally mounted on the frame and includes an ejecting arm for actuating the ejector rod associated therewith and a follower arm engaging the cam associated therewith and carried by the rocker shaft.

Each cam is substantially in the form of a cylindrical segment having an outer arcuate surface and pivoted at one end to the rocker shaft and carrying an adjusting means at its other end for changing the position of its arcuate surface relative to the axis of the rocker shaft.

BRIEF DESCRIPTION OF DRAWINGS The drawings forming a part of this application show an embodiment of a machine according to the invention, which embodiment is illustrated by way of example.

In the drawings:

FIG. 1 is a more or less diagrammatic plan view of the machine showing the relative locations and relationships bet-ween the principal parts of the machine;

FIG. 2 is a diagrammatic side elevational view of the machine shown in FIG. 1;

FIG. 3 is a sectional view taken along the line IIIIII of FIG. 1, drawn on an enlarged scale and illustrating one position of one of the adjustable cams;

FIG. 4 is a view similar to that of FIG. 3 showing the adjustable cam and associated elements in a different position effected by the rotation of the rocker shaft;

FIG. 5 is a view similar to that of FIG. 3 showing the cam adjusted to a different position from that shown in FIG. 3;

FIG. 6 is a diagrammatic view partly in section showing the adjustment possibilities of the adjustable cams according to the invention;

FIG. 7 is a rear view on an enlarged scale of the rocker shaft, adjustable cams, cam followers and ejecting levers; and

FIG. 8 is an elevational view of the rocker shaft with the cams and other devices removed.

DESCRIPTION OF PREFERRED EMBODIMENT The upsetting machine embodying the invention, and as shown in FIGS. 1 and 2 comprising a frame 5, a crankshaft 4 carrying a flywheel 3 driven by an electric motor 1 through V-belts 2. The crankshaft 4, through its crank and connecting 7 gives a reciprocating movement to a carriage 8, to which die-retaining members 9 are attached. The dies cooperate with matrices 10 arranged in a retaining member 11 fixed in the frame 5 as shown more in detail in FIG. 3.

The series of dies and matrices together form the four forming stations, as indicated in FIGS. 1 and 7, in which workpieces are subjected to an upsetting operation, the

3 workpieces being transferred from one station to another by a known type mechanism not shown. After the workpieces have been upset in the matrices they must be ejected, and this is done by an improved ejecting mechanism described hereinafter.

According to the showing in FIGS. 1, 2, 3 and 7, the crankshaft 4 is provided with an eccentric 12 and drive rod 13 which gives an oscillating movement to a rocker shaft 15 by a forked arm 14 fixed to the rocker shaft in the usual Way. The rocker shaft is mounted in bearings and extends across the end of the frame 5, as shown. Adjustable ejector cam discs 16 are provided on the rocker shaft 15 for the respective forming stations and they are respectively engaged by cam follower rollers 17 located at the lower ends of arms 18 of ejecting levers 18a mounted on a shaft 19 for oscillating rotation by the respective cams 16.

Each lever 18a includes an upwardly-extending ejector arm 20 provided with an adjusting bolt 21 threaded therethrough which acts on an ejector rod

system comprising rods

22 and 23 and ejector pin 23a to eject a workpiece 24 from a matrix 10 (FIGS. 3 and 4). A compression spring 25 extending around the rod 23- and acting against its enlarged head, at each station, keeps the corresponding follower roller 17 in engagement with its cam 16 and effects the return of the

arms

18 and 20 after a workpiece has been ejected. The timing of the ejecting mechanism is such that the ejecting operation starts when the carriage 8 starts its return stroke and is completed when the rocker shaft 15 takes the position indicated in FIG. 4, in which the roller 17 is on the highest part of the ejecting cam 16, and the small ejector pin 23a has ejected the workpiece 24.

Now, if a shorter workpiece 24 is formed in and ejected from one of the matrices 10, the stroke of the ejecting cam 16 must be decreased, as illustrated in FIG. 5. For this purpose the cams 16, in the form of a shaped segment or disc as shown, are respectively located in grooves 27 in the rocker shaft 15 and pivoted from one end of a pivot pin 26 extending through the walls of the grooves. Each cam 16 is biased toward the position shown in FIG. 3 by a retaining tension spring 28 located in the cam groove 27 and fixed to a pin 29.

An adjusting screw or bolt 31 is threaded through the end of each cam 16, opposite to its pivoted end, with its point bearing against an abutment 30 set in the rocker shaft 15. When rotated in one direction the adjusting screw 31 pivots the cam 16 outwardly, for example, from the position shown in FIG. 3 toward that of FIG. 5, against the tension of the spring 28 to decrease the stroke of cam 16 and the length of the ejecting stroke of the ejector rod system. When the bolt 31 is rotated in the opposite direction the spring 28 will pull the cam 16 toward the axis of the rocker shaft 15 and increase the stroke length of the ejector rod system.

Since the oscillating motion of the rocker shaft 15 is derived from the crankshaft 4, it and the cam discs 16 mounted thereon will carry out a continuous oscillating movement. However, since the ejector rod system must remain stationary during an upsetting operation, the camming surface of each cam 16 includes a predetermined portion with a steady radius for the roller 17 with respect to the axis of the rocker shaft 15. When the roller 17 runs on such a portion, illustrated by the arc 3 2 in FIG. 6, as the shaft 15 rotates through this arc, the ejecting lever 18a and the ejector rod system remain stationary.

In FIG. 6 the complete arc of movement is represented by the line 33 and this includes the arc 32 representing the stationary position, which is maintained for a predetermined period at each setting of the ejecting length. This is apparent from a comparison of the full and dotted line positions of the cam 16 and the roller 17. FIG. 6 is used to represent the different positions of a roller 17 on the camming surface of a cam 16 at different settings, while as a matter of fact the rocker shaft 15 rotates relative to the roller 17 through the angles indicated.

While the details of the ejector rod system is not a claimed part of the present invention it will be noted that during a pressing operation the enlargement on the rod 23 bears against an adjustable sleeve, around rod 22 and threaded into another sleeve located in the frame 5, as shown in FIGS. 3 and 5. The rods 22 and 23- may be a single rod. The sleeve around the rod 22 is adjusted in or out according to the depth desired for the cavity of the matrix.

I claim:

1. An ejector mechanism for a machine for upsetting workpieces for the production of bolt blanks in several stages, said machine being of the type including a frame having a fixed matrix arranged therein for receiving a portion of a workpiece, a reciprocal carriage mounted in the frame carrying a die adapted to cooperate with said matrix, and said ejector mechanism comprising an ejector rod guided in said fixed matrix, said ejector rod being driven by means of a lever including a follower arm pivotally mounted in the frame of the machine, a rockable rocker shaft carrying a cam, a follower roller carried by said follower arm and engageable by said cam of the rocker shaft, wherein said cam includes means providing a curved arcuate camming surface engaging the follower roller on the follower arm, said rocker shaft being driven synchronously with the main drive of the machine, a portion of said cam being adjustable, means for adjusting said cam portion including a single screw means arranged so as to vary the starting position of the ejection operation with regard to the axis of the rocker shaft by rotation of said cam portion about a pin parallel to the axis of the rocker shaft, said cam having a camming surface comprising a semi-cyclindrical segment and in which said adjustment about the rocker shaft can be carried out by means only of said one adjusting screw in contact with the rocker shaft, said adjustable cam portion having a circumferential portion which is developed in such a way that the follower roller always is stationary on said circumferential portion, so that no movement of the ejecting arm of the lever during the movement of the follower roller along said portion is produced.

2. An ejector mechanism as claimed in claim 1, wherein the adjusting screw is threaded edgewise through said cam portion remote from its pivot pin for adjusting the position of the camming surface relative to the axis of the rocker shaft.

3. An ejector mechanism as claimed in claim 2, including a spring means on the rocker shaft for biasing the adjusting screw into contact with the rocker shaft.

4. An ejector mechanism as claimed in claim 1, wherein the rocker shaft is provided with a cam groove extending generally transversely of the axis of the rocker shaft and in which the cam is mounted on said pin.

5. An ejector mechanism as claimed in claim 4, wherein said cam portion is in the form of a generally semicylindrical segment one end of which is pivoted on said pin which extends through the side walls of the cam groove in the rocker shaft.

6. An ejector mechanism as claimed in claim 2, wherein the cam is substantially in the form of a flattened semicylindrical segment pivoted from one end directly to said rocker shaft, said adjustable portion of the cam having a projection at its end opposite said pivot through which an adjusting screw extends to engage the rocker shaft.

References Cited UNITED STATES PATENTS 733,220 7/1903 Krebs 74-568 2,323,737 7/19'43 Tritle 74-568 2,324,767 7/ 1943 Cote 74-568 3,171,144 3/1965 Maistros 10-12 CHARLES W. LANHAM, Primary Examiner L. A. LARSON, Assistant Examiner