US 3730659 A
A work station positioner for a powder compacting press operable to move through three separate operations, namely, fill, press and eject, in which there is provided an improved controllably vibratable powder dispenser mechanism actuable during the fill operation. The amplitude of vibration of the powder dispenser and the frequency with which it is vibrated are selectively adjustable for the particular type and particle size of powder material being used.
Claims available in
Description (OCR text may contain errors)
United States Patent 91 Smith et al.
 POWDER DISPENSER FOR A POWDER COMPACTING PRESS  Inventors: Joseph E. Smith, Birmingham; Georges D. DeTroyer, Grosse lle,
both of Mich.
 Assignee: Wolverine-Pentronix, lnc., Lincoln Park, Mich.
[221 Filed: Oct. 4, 1971  Appl.No.: 185,932
 US. Cl. ..425/78, 425/258, 425/406  Int. Cl ..B29c 3/00  Field of Search ..425/78, 350, 351,
 References Cited UNITED STATES PATENTS 3,328,840 7/1967 Vinson ..425/78 51 May 1,1973
3,382,540 5/1968 Van De Molen et a1. ..425/78 3,561,056 2/1971 Smith et al. ..425/414 3,645,658 2/1972 De Troyer...
Primary Examiner-J. Howard Flint, Jr. Attorney-R0bert C. Hauke et a1.
57 ABSTRACT A work station positioner for a powder compacting press operable to move through three separate operations, namely, fill, press and eject, in which there is provided an improved controllably vibratable powder dispenser mechanism actuable during the fill operation. The amplitude of vibration of the powder dispenser and the frequency with which it is vibrated are selectively adjustable for the particular type and particle size of powder material being used.
15 Claims, 4 Drawing Figures 2 Sheets-Sheet 1 FIGI FIG. 2 INVENTORS Jose/w E. SMITH 660K665 D 057%(0 BY//flw/Q XW Farm ATTORNEYS POWDER DISPENSER FOR A POWDER COMPACTING PRESS BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to precision powder compacting presses having punch and die sets and a work station positioner adapted to move through successive fill, press and eject operations in one or more die cavities in which there is provided an improved powder dispenser for operation during the fill stage.
2. Description of the Prior Art The present invention represents an improvement over compacting presses in which the powder dispenser normally was oscillated at a limited range of frequen cies or at a single fixed frequency. The apparatus disclosed in the present application is particularly adaptable to those powder compacting presses that are used to manufacture cores, beads, pellets and the like, which are made of powdered ferrite, glass or other similar powder substances. The present invention is operable in connection with either a single or a multiple cavity die setup. The finished articles after completion of the press operation are automatically ejected from the die cavity by means of a pickup head operating. under a vacuum and dropped through discharge ports or onto a conveyor.
The principal portion of the press mechanism to which the present invention is related is the work station positioner assembly which is an integral part of the press and mounted in a manner such as to be angularly transversely movable over the die plate. The positioner assembly has as its three essential operating parts a powder dispenser, an anvil and a pickup head. The powder dispenser may be continuously provided with a press which is suitable for incorporation of the present invention.
SUMMARY OF THE INVENTION The present invention provides a novel and improved powder dispenser and actuating mechanism therefor with separately adjustable means for controlling the amplitude and frequency of vibration of the dispenser.
The vibration control mechanism for the powder supply of powder from a storage means by means of a flexible tubing. The dispenser is first positioned over the die cavity to be filled with powder and the punch at the lower end of the cavity is displaced downwardly so as to draw a predetermined amount of powder within the die cavity. The dispenser is then removed from its position above the die cavity by an indexing movement of the station positioner assembly and the anvil is next in turn positioned over the die cavity.
While the anvil is clamped in place, the powder in the die cavity is compacted against the anvil coincident to the upward motion of the punch tool. The anvil is then removed from its position above the die cavity or cavities and is replaced by the pickup head after a further indexing motion of the work station positioner. The punch may then be displaced upwardly so as to bring its upper end in flush alignment with the upper surface of the die plate so that the finished compacted article is free to be removed from the cavity. Along with the angular return motion of the station positioner to its initial fill position, the pickup head is removed from over the die cavity and disposed over a discharge aperture to provide for removal of the finished articles.
Reference is made to U.S. Pat. No. 3,574,892 issued to Joseph E. Smith for Powder Compacting Press and to U.S. Pat. No. 3,561,056 issued to Joseph E. Smith et al. for Tool Set for Powder Compacting Press, both of which are of common ownership with the present application. These patents and the pertinent parts of their disclosures are hereby incorporated by reference as showing the essential parts of a dispenser is automatically activated responsive to the station positioner assembly being indexed to the fill position over the die cavity. A manual adjusting means is used to preset the degree of eccentricity of a drive cam for oscillating the arm on which the powder dispenser itself is mounted. Frequency of vibration is adjusted through a valve means operative to control the speed of rotation of a drive air motor.
BRIEF DESCRIPTION OF THE DRAWINGS The present invention will be understood by reference to the accompanying specification and to the appended drawings in which like numerals are used to identify identical parts appearing throughout the several views, and wherein:
FIG. 1 is a top plan view of a press work positioner assembly incorporating the present invention;
FIG. 2 is a fragmentary, cross-sectional view of the die plate showing the die cavity and punch;
FIG. 3 is a side elevational view of the apparatus of FIG. 1 taken along the section line 3-3; and
FIG. 4 is an end view taken along the line 4-4 of FIG. 3.
DESCRIPTION OF THE PREFERRED EMBODIMENT With particular reference to the FIG. 1 drawing, there is shown a work station positioner assembly 10 including a plate 11 as it-is mounted near the top of shaft 12. The top of a die plate 14 is shown with the positioner assembly plate shown in solid line configuration indexed counterclockwise to the fill position..lt will be understood that the positioner assembly 10 is operated in synchronization with a lowerpunch assembly and the timing of the movements of the work positioner assembly are all controlled by a mechanism which is cam operated through a main shaft (not. shown). The details of the operating mechanism for the press is not shown in the interest of brevity, but reference may be made to the above mentioned patents for a description of its parts and operation.
With further reference to FIG. 1., it will be seen that the positioner assembly carries at its lower edge, viewed from left to right, a powder dispenser 16 and container 16a, an anvil 18 and a pickup head 20. The outline of the upper end of a die cavity 22 is shown in the die plate 14. The lower end of the powder dispenser 16 has its opening aligned with the upper end of the die cavity 22.
FIG. 2 shows the internal construction of the die plate 14 which includes the die cavity 22 and a die bushing 23a. A punch 23 is shown as it is positioned in the die cavity 22. The powder 25 is shown as it is being introduced from the lower end of the powder dispenser 16 into the die cavity 23.
It is important that the powder dispenser 16 with its container 16a be oscillated during the fill operation. It is desirable that there be an appropriate agitation of the powder dispenser 16 so that the powder will uniformly fill the die cavity 22 from the top of the punch 23 to the upper surface of the die plate 14. The present invention will be seen to provide a mechanism which allows for independent amplitude and frequency adjustment of the vibration of the powder dispenser 16.
The anvil 18 is positioned adjacent to the powder dispenser 16 along the lower edge of the plate 11. The anvil l8 closes the top of the die cavity while the punch 23 is being driven upwardly to provide a suitable com pacting force to the powder 25 in the die cavity 22.
The pickup head 20 is finally indexed above the die cavity 22 and the part that has just been compacted. The pickup head 20 may be attached to a source of vacuum to provide for lift and removal of the finished part from the die cavity 22 as a result of upward motion of the punch 23 and for discharge of the finished part through a discharge port, or in some cases to a continuous conveyor. This discharge would normally occur when the work station positioner assembly has returned to its fill position, at which time the vacuum pressure exerted through the pickup head would be changed to a positive air pressure to provide for a discharge of the finished part.
Now with further reference to FIG. 1, there is shown at the left hand side of the drawing a vibrating mechanism for the powder dispenser l6. Included is an arm 24 which is pivotally supported on the upper surface of the work positioner assembly plate 11 on a mounting post 26 extending upwardly therefrom. The post 26 is fastened to the plate 11 by a screw fastener 28. The post 26 further has a central opening 30 adapted to receive one end of a X-spring bearing 31. The bearing 30 extends through a central opening 32 in the arm 24 and the two are pinned together by a stud 33, as best shown in FIG. 3. This mounting structure provides a pivot point about which the arm 24 can freely oscillate. A pair of cam followers 38 and 40 are mounted, spaced one from the other, at the upper end 42 of the arm 24. The travel of the two cam followers 38 and 40 through the several positions as the work positioner assembly 10 is indexed is shown in dash line configuration. In the upper left hand position shown, the pickup operation is being performed. In the middle position of the cam followers 38 and 40, the press operation is performed. In the lower solid line position of the arm 24, the actual fill operation is being performed with the powder 25 being discharged from the powder dispenser 16 to the die cavity 22. Also shown at the upper left side of the drawing of FIG. I is the mechanism used to activate the arm 24 and thus vibrate the powder dispenser 16. The actuating mechanism is identified generally by the numeral 44 and includes as its principal element a drive cam 46. The drive cam 46 is shown in the manner in which it engages the two cam followers 38 and 40 at the upper end'of the support arm 24 so that in accordance with the eccentricity of the cam 46 there will be a variable amplitude oscillation of the arm 24 about its central pivot point provided by the X-spring bearing 31. The detail of the drive cam 46 and its operating mechanism will be best shown in FIG. 3 hereinafter.
Also shown in FIG. 1 are the three cam adjusting screws 48a, 48b and 480, the relative tightening of which are used to hold and to release the cam 46 to adjust the degree of eccentricity and hence the amplitude of oscillation of the support arm 24 and the powder dispenser 16.
Now with reference to FIG. 3, it will be seen that the powder dispenser T16 is maintained in flush relationship with the upper surface of the die plate 14 as it is moved arcuately through the three index positions along with the synchronized movement of the positioner assembly 10. It will be understood that the upper end of the powder container 1.6a is normally connected to a reservoir of powdered material 25. The basic driving mechanism for the vibrator is the eccentric cam 46 already referred to in connection with FIG. 1. It will be noted that the FIG. 3 drawing, taken along the section line 33, shows the powder dispenser 16 in its intermediate position just prior to entering the fill position. The parts are thus shown with the cam follower 40 visible as it is still maintained out of driven engagement with the cam 46. The rotative drive of the eccentric cam 46 is taken from a pneumatic motor 50, which motor in turn is connected to a source of pressurized air 52 through an adjustable valve means 54. It will be seen that through the setting of the valve 54 it is possible to adjust the speed of rotation of the motor 50 and hence the frequency of vibration of the powder dispenser 16. The motor 50 is mounted on a bracket 56, which is attached to a press frame plate 58 through a plurality of screws 60, one of which is shown. Attached at the end of the output shaft 62 of the motor 50 is a cap 63 having a first relatively large diameter portion 65 and a second reduced diameter eccentric end portion 66. The cap 63 is fixed to a threaded end 67 of the output shaft 62 with an O-ring 68 therebetween. The eccentric cam 46 is fitted over the reduced diameter eccentric end portion 66 of the cap 63 and held in place by a threaded fastener or retainer 70. One of the three adjusting screws 48c is shown extending through the top of the eccentric cam 46 with its'projecting end in abutment with the end of the large diameter portion 65 of the cap 63. j
The drawing of FIG. 4 illustrates the manner in which the degree of eccentricity of the cam 46 may be changed through a distance D after loosening of the three adjusting screws 48a, 48b and 480 and rotating manually the cam 46 about its axis, and tightening the screws 48a, 48b and 48c with their end firmly engaging the end of the large diameter portions 65 of the cap 63 so as to wedge the end face of the cam 66 against the lower surface of the retainer 70.
It will thus be seen that the present invention provides a novel and substantially improved vibration mechanism for a powder dispenser used in a powder compacting press. The present invention is of particular utility and exhibits special advantages when it is incorporated in a multiple station positioner assembly indexed between its several operating positions relative to the die cavity or cavities. There is further provided a mechanism for automatically activating and initiating the vibration of the powder dispenser as soon as it has been indexed to the appropriate fill operation above the die cavity.
What is claimed is:
1. In a powder compacting press including at least one die cavity and a station positioner assembly plate mounted above said die cavity for providing successive fill, press and eject operations in synchronization with a mating punch positioned at the lower end of said cavity, said positioner assembly including a powder dispenser, an anvil and a pickup head, each successively alignable with said die cavity during one of aforesaid operations, the improvement comprising:
a rotatable drive shaft having a cam mounted proximate one end thereof;
a support arm for said powder dispenser mounted on said assembly plate, said arm having a pivot point intermediate its ends, said arm further having a pair of cam followers at one end engageable in driven relationship with said cam during alignment of said dispenser with said cavity in said fill position to provide an appropriate vibration of said powder dispenser.
2. The combination as set forth in claim 3 wherein a separate adjusting means is provided for controlling the frequency of the vibration of said powder dispenser, said means comprising a variable RPM motor operatively connected to and controlling the speed of rotation of said rotatable drive shaft.
3. The combination as set forth in claim ll wherein a mounting post is fixed to the upper surface of said plate wherein a flexible X-spring type bearing is used to mount said am on said post.
4. The combination as set forth in claim 2 wherein said variable RPM motor comprises a pneumatic motor and said adjusting means comprises an air valve connected between said motor and a pressurized air source.
5. The combination as set forth in claim ll wherein an adjusting means is included for varying the degree of eccentricity of said cam with respect to said shaft whereby the amplitude of vibration of said powder dispenser is selectively controlled.
6. A powder compacting press including a die cavity and a station positioner assembly indexably mounted above said die cavity, said assembly plate having mounted thereon a powder dispenser, an anvil and a pickup head, each successively alignable with said die cavity during its operation, and a means for vibrating said dispenser, comprising:
a pivotable mounting arm having said dispenser fixed thereto and having at least one cam follower fixed to it proximate one end;
a rotatable shaft having a cam engageable with said cam follower for driving it to vibrate said arm and said powder dispenser; and
a means for adjusting the degree of movement of said cam relative to said cam followers for controlling the amplitude of vibration of said dispenser.
7. The combination as set forth in claim 6 wherein said cam is mounted on the end of said shaft and wherein a means is operably connected to said cam for controlling its degree of eccentricity relative to said shaft for selectively changing the amplitude of vibration of said arm and said dispenser.
8. The combination as set forth in claim 6 wherein a means is operably connected to said shaft for controlling its speed of rotation and therefore the frequency of vibration of both said am and said dispenser.
9. The combination as set forth in claim 8 wherein said shaft comprises the output shaft of a pneumatic motor having its input connected to a pressurized air source and wherein said means for controlling its speed or rotation comprises a flow control valve connected thereto.
10. A powder compacting press including a die cavity and a station positioner assembly means indexably mounted above said die cavity, said positioner assembly means having mounted thereon a powder dispenser, an anvil and a pickup head, each successively alignable with said die cavity during press operation, and a means for vibrating said dispenser comprising an arm fixed to said dispenser, said arm pivotably mounted on said positioner assembly means, and said arm further having a pair of cam followers mounted on it spaced one from the other proximate one end and spaced from said dispenser, a rotatable drive shaft and a drive means therefore mounted on said press and spaced from said positioner assembly means, said shaft further having a cam projection engageable with said cam followers, engageable in driving relationship with said cam responsive to the rotation of said arm with said plate into the powder dispenser alignment with said die cavity.
1 l. A powder dispenser assembly for use in a powder compacting press including a die cavity, said powder dispenser movable between an inactive position away from said cavity and an active position proximate said cavity for fill operation, wherein the invention comprises:
a mechanism for vibrating said dispenser, including a rocltable lever, said powder dispenser operatively connected to said lever;
an actuating means operatively connected to and controlling the rocking movement of said lever; and
an adjusting means operatively connected to said actuating means for controlling its amplitude of vibration.
12. The combination as set forth in claim If wherein a variable speed drive motor is operably connected to said cam for varying its speed of rotation and hence the frequency of vibration of said arm and said powder dispenser.
13. The combination as set forth in claim 11 wherein said cam is mounted on the end of said rotatable shaft and wherein a plurality of axially adjustable fastening means are included for varying the degreeof eccentricity of said cam relative tosaid shaft and thereby selectively varying the amplitude of vibration of said dispenser.
M. The combination as set forth in claim ill wherein an indexable plate is used for moving said dispenser between its active and inactive position, and wherein said arm is rockably mounted on said plate by a flexible X-spring bearing.
15. The combination as set forth in claim 1 1 wherein said rockable lever comprises a pivotable arm, said powder dispenser mounted on one end of said arm and wherein said actuating means comprises at least one cam follower mounted on the other end of said arm, said actuating means for said arm comprising a rotatable cam engageable in driving relationship with said cam follower to provide a selectively variable amplitude of vibration of said dispenser.