Claims
- 1. A machine for making cigarette filters from filter tow, including means for feeding filter tow towards a rod forming section; means for laterally compressing the filter tow to the cross-section of the finished rod, including a tongue which shapes and compresses the tow to the final cross-section; and means associated with the downstream end of the tongue for sensing the pressure drop through the tow in a region where the tow has nearly reached its final cross-section.
- 2. A machine according to claim 1 including means for altering the tow feed rate by a variable amount dependent upon the pressure drop measurement so as to maintain the pressure drop substantially constant.
- 3. A machine according to claim 1 in which the means for sensing the pressure drop comprises two longitudinally spaced pressure tappings in the tongue, and a comparator arranged to compare the pressure at the two pressure tappings.
- 4. A machine according to claim 3, including a suction conveyor arranged to compress the tow laterally before the tow passes under the tongue.
- 5. A machine according to claim 4 in which the suction conveyor is a suction wheel arranged to rotate adjacent to a web or tape carrying the tow so as to compress the tow in cooperation with the web or tape.
- 6. A machine according to claim 5 in which the suction conveyor is arranged to compress the tow approximately to its final cross-sectional area.
- 7. A machine according to claim 4, including a fluffing device arranged to blow air into the tow from the side before the tow is laterally compressed.
- 8. A machine according to claim 7 in which the fluffing device includes an annular air outlet through which air is blown into the tow from all sides.
- 9. A machine according to claim 1 in which the pressure drop sensing means comprises a pressure tapping in the tongue, a hollow member defining a pressure space adjacent to the outer surface of the tongue in the region of the pressure tapping, a pipe which is connected to the pressure space and to a supply of air at a pressure substantially higher than the pressure in the tongue, an orifice by which the pressure from the pipe is dropped as it enters the pressure space to a level slightly above the mean pressure within the tongue in the region of the pressure tapping, the space being connected to a pressure measuring device or pressure comparator.
- 10. A machine according to claim 1, including means for monitoring the pressure drop through the tow and for adjusting the tow feed so as to maintain the pressure drop substantially constant; a weight monitoring device arranged to monitor the rate of consumption of tow; and a tow stretching device arranged to stretch the tow to a variable extent before the tow is laterally compressed; and a stretch control logic circuit arranged to operate at spaced time intervals to increase or decrease the tow stretch by a predetermined step at each operation, depending upon whether the previous stretch adjustment step increased or decreased the tow consumption, so as to minimise the consumption of tow.
- 11. A machine for making cigarette filters from filter tow, including means for feeding tow towards a rod-forming unit; means for blowing air into the tow during its movement towards the rod-forming unit; a suction conveyor which is downstream of the blowing means and is arranged to compress the tow laterally while drawing air out of the tow; means downstream of the suction conveyor for sensing the pressure drop through the tow, including two longitudinally spaced pressure tapping means arranged in a tow-shaping tongue means; a comparator means arranged to compare the pressure at the two pressure tapping means; and means for adjusting the tow feed in response to the pressure drop sensor to maintain the pressure drop substantially constant.
- 12. A machine according to claim 11 in which the suction conveyor is arranged to compress the tow to substantially its final cross-sectional area and said tongue means is arranged to shape the tow to its final cross-section.
- 13. A machine for making cigarette filters from filter tow, including means for monitoring the pressure drop through the tow and for adjusting the tow feed so as to maintain the pressure drop substantially constant; a weight monitoring device arranged to monitor the rate of consumption of tow; and a tow stretching device arranged to stretch the tow to a variable extent before the tow is laterally compressed; and a stretch control logic circuit arranged to operate at spaced time intervals to increase or decrease the tow stretch by a predetermined step at each operation, depending upon whether the previous stretch adjustment step increased or decreased the tow consumption, so as to minimise the consumption of tow.
- 14. A method of making cigarette filters from filter tow, including the steps of feeding filter tow while blowing air into the tow to fluff up the tow, laterally compressing the tow while drawing air out of the tow, and then monitoring two longitudinally spaced pressure tapping means so as to determine a pressure drop through the tow, comparing the pressure at the two pressure tapping means, and using the pressure drop signal to control the tow feed so as to maintain the pressure drop substantially constant.
- 15. A machine for making cigarette filters from filter tow, including means for feeding filter tow towards a rod-forming section; means for laterally compressing the filter tow to the cross section of the finished rod, including a tongue which shapes and compresses the tow to the final cross section; and means for measuring the pressure drop through the tow, comprising two longitudinally spaced pressure tapping means in the tongue, and a comparator arranged to compare the pressures at the two pressure tapping means.
- 16. A machine according to claim 15, in which each pressure tapping means comprises means defining a pressure space adjacent to the outer surface of the tongue, a pipe which is connected to the pressure space and to a supply of air at a pressure substantially higher than the pressure in the tongue, an aperture formed in the tongue and communicating with the pressure space, and an orifice by which the pressure from the pipe is dropped as it enters the pressure space to a level slightly above the mean pressure within the tongue in the region of the aperture.
- 17. A machine for making rod-like articles of the cigarette industry from a filler material, including means for feeding the filler material toward a rod-forming section; means for laterally compressing the filler material to a cross section of a finished rod, including a tongue means for shaping and compressing the filler material to a final cross section; and means associated with the downstream end of the tongue means for sensing a pressure drop through the filler material in a region where the filler material has nearly reached its final cross section.
- 18. A machine according to claim 17, wherein said means for sensing a pressure drop comprises two longitudinally spaced pressure tapping means.
- 19. A machine according to claim 18, in which each pressure tapping means comprises means defining a pressure space adjacent to the outer surface of the tongue means, a pipe which is connected to the pressure space and to a supply of air at a pressure substantially higher than the pressure in the tongue means, an aperture formed in the tongue means and communicating with the pressure space, and an orifice by which the pressure from the pipe is dropped as it enters the pressure space to a level slightly above the mean pressure within the tongue means in a region of the aperture.
Priority Claims (2)
Number |
Date |
Country |
Kind |
27583/76 |
Jul 1976 |
GBX |
|
53688/76 |
Dec 1976 |
GBX |
|
Parent Case Info
This is a continuation of application Ser. No. 811,142 filed June 28, 1977 now abandoned.
US Referenced Citations (5)
Foreign Referenced Citations (2)
Number |
Date |
Country |
888479 |
Jan 1962 |
GBX |
1295864 |
Nov 1972 |
GBX |
Continuations (1)
|
Number |
Date |
Country |
Parent |
811142 |
Jun 1977 |
|