Releasable Punch Dampener

Abstract

A rotary tablet press has a rotating mold table and top and bottom punches, which can move reciprocally in punch guides, coaxially with the molds. The reciprocating motion of at least the bottom punches is cam-controlled and these punches are acted upon by a releasable punch dampener to prevent an overshoot of their movement and to ensure an action which is as free from wear. It is as maintenance-free as possible whilst maintaining constant damping of the bottom punches. The releasable punch dampener releases with one motion and has a linear release shaft with a release surface and a dampening surface.

Claims

1-20. (canceled)

21. A rotary tablet press turret comprising: a bottom punch guide mounted in the rotary tablet press turret; a bottom punch coaxially mounted in the bottom punch guide that is cam-controlled and moves from a stroke to a return stroke and back; a releasable bottom punch dampener for dampening the movement of the bottom punch mounted in the rotary tablet press turret and transverse to the bottom punch guide, the releasable bottom punch dampener comprising: a linear release shaft; wherein the linear release shaft has a proximate end and a remote end; wherein on the proximate end is a release device to move the linear release shaft; wherein on the linear release shaft is a release surface; wherein adjacent to the linear release surface is a dampening surface; wherein on the linear release shaft is a spring engaging surface with a spring mounted thereon; wherein the spring is biased to engage the dampening surface with the bottom punch; wherein when the dampening surface is engaged with the bottom punch, the bottom punch moves from the stroke to the return stroke and back along the bottom punch guide; and wherein when the dampening surface is engaged with the bottom punch, the motion of the bottom punch is dampened to prevent an overshoot of the stroke or return stroke movement.

22. The rotary tablet press turret of claim 21, wherein the releasable bottom punch dampener has an engaged position and a released position; wherein in the engaged position the spring acts on the spring engaging surface to move the dampening surface to engage with and dampen the bottom punch; and wherein in the released position the release device is engaged causing the dampening surface to move from the bottom punch and the release surface is moved proximate but not touching the bottom punch.

23. The rotary tablet press turret of claim 22, wherein the release surface is a narrowed portion of the release shaft and is an concave cutout surface approximately larger radius of curvature as the punch shaft; and wherein in the released position, the bottom punch does not touch the release surface.

24. The rotary tablet press turret of claim 23, wherein the concave cutout is circumferential.

25. The rotary tablet press turret of claim 24, wherein the dampening surface is angled and is a transition from the release surface to the release shaft to engage the bottom punch.

26. The rotary tablet press turret of claim 25, wherein the spring engaging surface is in an opening in the remote end of the release shaft in which the spring is nested.

27. The rotary tablet press turret of claim 26, wherein on the releasable bottom punch dampener between the proximate end of the release shaft and the release surface is a releasable bottom punch shoulder.

28. The rotary tablet press turret of claim 27, wherein the releasable bottom punch dampener is mounted in a dampener opening in the rotary tablet press turret; wherein the dampener opening peripherally intersects and is transverse to the bottom punch guide; wherein the dampener opening has an opening proximate end and an opening remote end; wherein the opening proximate end is at the exterior of the turret and engages fixedly with a mounting device; and wherein the mounting device has a longitudinal opening and the release shaft is moveably engaged in the longitudinal opening.

29. The rotary tablet press turret of claim 28, wherein the mounting device has a shoulder engaging surface that engages with the releasable bottom punch dampener shoulder, thereby holding the releasable bottom punch dampener in the dampener opening while allowing longitudinal motion of the releasable bottom punch dampener.

30. The rotary tablet press turret of claim 29, wherein the spring is a compression spring with one end mounted on the spring engaging surface and the other end mounted on the dampener opening remote end.

31. The rotary tablet press turret of claim 30, wherein the linear release shaft has an axis and is bilaterally symmetrical.

32. A rotary tablet press turret comprising: a bottom punch guide; a bottom punch coaxially mounted in the bottom punch guide that is cam-controlled and moves from a stroke to a return stroke and back; a releasable bottom punch dampener for dampening the movement of the bottom punch comprising: a linear release shaft; wherein the release shaft has a proximate end and a remote end; wherein on the proximate end the release shaft has a release device that moves the linear release shaft; wherein the linear release shaft has a release surface; wherein the linear release shaft has a dampening surface; wherein on the linear release shaft is a spring mounted on a spring engaging surface; wherein the releasable bottom punch dampener has an engaged position and a released position; wherein in the released position the release device is engaged causing the dampening surface to move away from the bottom punch and the release surface to be proximate but not touching the bottom punch; wherein the spring is biased to engage the dampening surface with the bottom punch; wherein when the dampening surface is engaged with the bottom punch, the bottom punch moves from the stroke to the return stroke and back along the bottom punch guide; and wherein when the dampening surface is engaged with the bottom punch, the motion of the bottom punch is dampened to prevent an overshoot of the stroke or return stroke movement.

33. The rotary tablet press turret of claim 32, wherein the release surface is a narrowed portion of the release shaft.

34. The rotary tablet press turret of claim 33, wherein the release surface is a concave cutout surface approximately larger radius of curvature as the bottom punch shaft.

35. The rotary tablet press turret of claim 34, wherein the concave cutout is circumferential.

36. The of claim 35, wherein the rotary tablet press turret dampening surface is curved and is a transition from the release surface to the release shaft to engage the bottom punch.

37. The rotary tablet press turret of claim 36, wherein the spring engaging surface is an opening in the remote end of the release shaft in which the spring is nested.

38. The rotary tablet press turret of claim 37, wherein on releasable bottom punch dampener between the proximate end of the release shaft and the release surface is a releasable bottom punch dampener shoulder.

39. A rotary tablet press turret for a bottom punch comprising: a bottom punch guide mounted in the rotary tablet press turret; a bottom punch coaxially mounted in the bottom punch guide that is cam-controlled and moves from a stroke to a return stroke and back; a dampener opening in the rotary tablet press turret; wherein the dampener opening peripherally intersects and is transverse to the bottom punch guide; a releasable bottom punch dampener for dampening the movement of the bottom punch mounted in the dampener opening, the releasable bottom punch dampener comprising: a linear release shaft; wherein the release shaft has a proximate end and a remote end; wherein on the proximate end the release shaft has a release device that moves the linear release shaft; wherein the linear release shaft has a release surface; wherein the linear release shaft has a dampening surface; wherein on the linear release shaft is a spring mounted on a spring engaging surface; wherein the releasable punch dampener has an engaged position and a released position; wherein in the engaged position the spring acts on the spring engaging surface to cause the dampening surface to engage with and dampen the bottom punch; wherein in the released position the release device is engaged causing the dampening surface to move away from the bottom punch and the release surface to be proximate but not touching the bottom punch; wherein the spring is biased to the engaged position; wherein the release surface is a concave cutout surface approximately larger radius of curvature as the bottom punch shaft; wherein the concave cutout is circumferential; wherein the dampening surface is curved; wherein the spring engaging surface is an opening in the remote end of the release shaft in which the spring is nested; wherein between the proximate end of the release shaft and the release surface is a shoulder; wherein the dampener opening has an opening proximate end and an opening remote end; wherein the opening proximate end is at the exterior of the turret and engages fixedly with a mounting device; wherein the mounting device has a longitudinal opening and the release shaft is moveably engaged in the longitudinal opening; wherein the mounting device has a shoulder engaging surface that engages with the releasable bottom punch dampener shoulder, thereby holding the releasable bottom punch dampener in the dampener opening while allowing longitudinal motion of the releasable bottom punch dampener; and wherein the spring is a compression spring with one end mounted on the spring engaging surface and the other end mounted on the dampener opening remote end.

40. The rotary tablet press turret of claim 39, wherein the release device is a depressible shaft which is axially aligned with the linear release shaft.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] FIG. 1 is a horizontal cutaway view of the releasable punch dampener in the engaged position mounted in the turret of a rotary tablet press; and

[0015] FIG. 2 is a vertical cutaway view of the releasable punch dampener in the engaged position mounted in the turret of a rotary tablet press.

[0016] Further areas of applicability of the present invention will become apparent from the detailed description provided hereinafter. It should be understood that the detailed description and specific examples, while indicating the preferred embodiment of the invention, are intended for purposes of illustration only and are not intended to limit the scope of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] The following description of the preferred embodiment(s) is merely exemplary in nature and is in no way intended to limit the invention, its application, or uses. In a preferred embodiment, as shown in FIGS. 1 and 2, the releasable punch dampener 100 has a release shaft 6 having a release shaft proximate end 2 and a release shaft remote end 4. On the proximate end is a release device 8. The release device 8 shown in FIG. 1 is a depressible shaft. However, the release device can a screw device or other means of moving the releasable shaft longitudinally.

[0018] In a preferred embodiment, the release device 8 is a depressible shaft which is axially aligned with the release shaft. The proximate end of the release shaft projects above the turret 22 a distance sufficient to move the releasable punch dampener from the engaged position to the released position when the release device is engaged. Positioned on the release device and proximate the release surface is a shoulder 12 which, when mounted acts to anchor the releasable punch dampener in the turret. In a preferred embodiment, the releasable shaft has an axis and is bilaterally symmetrical allowing longitudinal movement from the engaged position to the released position by activation of the release device.

[0019] On the release shaft is a release surface 10. In a preferred embodiment, the release surface is a narrowed portion of the release shaft and is a concave cutout surface approximately larger radius of curvature as the punch shaft so that in the released position, the punch does not touch the release surface. In a more preferred embodiment, the concave cutout is circumferential. Alternatively, the release surface 10 is a straight-edged cutout that provides an opening greater than the punch, so that when in the released position, the punch does not touch the release surface. Optionally, between the proximate end of the release shaft and the release surface is a shoulder 12. Adjacent to the release surface is a dampening surface 14. The dampening surface can be curved to engage the punch, or it can be angled. Preferably, the dampening surface is angled and is a transition from the release surface to the release shaft. The curved surface is effective in engaging the punch.

[0020] On the remote end 4 of the release shaft is a spring engaging surface 16 with a spring 18 mounted therein, such as a compression spring or a tension spring. Most preferably, the spring 18 is a compression spring. Preferably the engaging surface 16 is an opening 17 in the remote end 4 of the release shaft in which a spring is nested. Other tensioning devices can be used and positioned in other parts of the release shaft. In a preferred embodiment, the spring, in a relatively untensioned or uncompressed biased state, holds the releasable punch dampener in the engaged position. In the relatively untensioned or uncompressed biased position, the spring has some tension or compression applied to use the engaged dampener position to dampen the movement of the punch. In the released position greater tension or compression is applied to the spring using the release device 8.

[0021] In a preferred embodiment, the releasable punch dampener 100 is mounted in a dampener opening 20 in a rotary tableting press turret 22, wherein the opening peripherally intersects and is transverse to the lower punch guide 24, wherein the dampener opening has an opening proximate end 26 and an opening remote end 28, wherein the opening proximate end is at the exterior of the turret 30 and engages fixedly with a mounting device 32 such as a mounting screw. Preferably, the opening proximate end is threaded to engage with the mounting device 32. The releasable punch dampener release shaft 6 engages movingly through a longitudinal opening 34 in the mounting device and the release device 8 projects outward from the exterior of the turret 30. Preferably, the mounting device has a shoulder engaging surface 36 that engages with the shoulder 12 of the punch dampener, thereby holding the punch dampener in the dampener opening while allowing longitudinal motion of the releasable punch dampener. Preferably, at the remote end of the dampener opening, the spring of the mounted releasable punch dampener extends into a spring compression gap 38. Preferably, the compression gap is sufficiently large as to allow at least some of the spring, when the releasable punch dampener is released, to fit in the gap. Preferably, the spring is a compression spring with one end mounted on the spring engaging surface and the other end mounted on the opening remote end.

[0022] When the releasable punch dampener is used, in the engaged and relatively untensioned or uncompressed state and the release device projects outward from the turret, the dampening surface intersects the punch and dampens its motion. In the released state and the release device is depressed, the spring is compressed, the dampening surface moves away from the punch shaft, and the release surface moves proximate the punch shaft, thereby releasing the punch from the dampening effect.

[0023] The embodiments were chosen and described to best explain the principles of the invention and its practical application to persons who are skilled in the art. As various modifications could be made to the exemplary embodiments, as described above with reference to the corresponding illustrations, without departing from the scope of the invention, it is intended that all matter contained in the foregoing description and shown in the accompanying drawings shall be interpreted as illustrative rather than limiting. Thus, the breadth and scope of the present invention should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims appended hereto and their equivalents.