GB2372071A - Desmodromic valve mechanism - Google Patents
Desmodromic valve mechanism Download PDFInfo
- Publication number
- GB2372071A GB2372071A GB0029048A GB0029048A GB2372071A GB 2372071 A GB2372071 A GB 2372071A GB 0029048 A GB0029048 A GB 0029048A GB 0029048 A GB0029048 A GB 0029048A GB 2372071 A GB2372071 A GB 2372071A
- Authority
- GB
- United Kingdom
- Prior art keywords
- valve
- lever
- mechanism according
- valve mechanism
- track
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
- F01L1/30—Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of positively opened and closed valves, i.e. desmodromic valves
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Valve Device For Special Equipments (AREA)
Abstract
A valve mechanism comprising; a valve having a valve stem which is located for axial movement in a valve guide and a valve head adapted at one extreme of movement of the valve to locate against and close a valve seat; characterised in that a valve lever (20) is pivotally mounted at one end (21) and attached adjacent the other end (23) to the end (22) of the valve stem (12) remote from the valve head (13); said valve lever (20) defining a track (25); a drive pin assembly (40; 60) consisting of a retractable pin (39;65) mounted within a housing, having a first position which is engaged with, and a second position which is disengaged with said track, with control means to move between said first and second positions and drive means (30, 35; 61) to drive said drive pin assembly (40; 60) in oscillatory manner, said track (25) having a first portion (28, 62) which, when the valve (11) is closed and the retractable pin 39 is in said first position, coincides with the path of the retractable pin (39; 65) and a second portion (26, 27; 63) which diverges from the path of the retractable pin (39; 65), so that engagement of the second portion (26, 27; 63) by the retractable pin (39: 61) will cause the valve lever (20) to move opening and closing the valve (11). Preferably the mean position of oscillation of the drive pin (39) is adjustable so that the duration and amplitude of valve opening may be varied. In a reciprocating four stroke engine application the oscillatory frequency of the drive pin assembly (40) is the same as the frequency of rotation of the crank. The retractable pin 39 is engaged in the drive track (25) on alternate cycles of the crankshaft.
Description
VALVE MECHANISM
The present invention relates to valve mechanisms and in particular. although not exclusively, to valve mechanisms for internal combustion engines
According to one aspect of the present invention a valve mechanism comprises a valve having a valve stem which is located for axial movement in a valve guide and a valve head adapted at one extreme of movement of the valve to locate against and close a valve seat; characterised in that a valve lever is pivotally mounted at one end and attached adjacent the other end to the end of the valve stem remote from the valve head; said valve lever defining a track; a drive pin assembly consisting of a retractable pin mounted within a housing, having a first position which is engaged with, and a second position which is disengaged with said track, with control means to move between said first and second positions, and drive means to drive said drive pin assembly in an oscillatory manner, said track having a first portion which, when the valve is closed and the retractable pin is in said first position, coincides with the path of the retractable pin and a second portion which diverges from the path of the retractable pin, so that engagement of the second portion by the retractable pin will cause the valve lever to move opening and closing the valve.
The mechanism described above provides desmodromic action, the valve lever controlling movement of the valve in both directions, providing that the operation of moving the retractable pin between the two positions is achieved whilst the valve is closed. There is consequently no need for the return springs used in conventional poppet valve mechanisms and the inherent disadvantages of such mechanisms, in particular valve bounce, are avoided and the mechanism may consequently be run at faster speeds.
With this mechanism, the duration and amplitude of the valve opening depends upon the portion of the track engaged by the retractable pin as it oscillates, this may be adjusted by varying the mean position of oscillation of the drive pin assembly.
According to a preferred embodiment the frequency of oscillation of the drive pin assembly is the same as the frequency of rotation of the crankshaft in a four stroke engine. The retractable pin disengages with the track on alternate cycles, the movement between the first position and the second position and
back occuning during the period when the valve is shut and the retractable pin is in, or adjacent to the first portion of the track. Means might be provided to maintain the valve in the closed position whilst the retractable pin is disengaged.
According to a further embodiment of the invention the retractable pin could be disengaged from the valve lever track in order to disable an engine cylinder or number of cylinders on a multi cylinder engine.
Various embodiments of the invention are now described, by way of example only, with reference to the accompanying drawings, in which :
Figures lA to IE are a diagrammatic illustration of a valve mechanism in accordance with the present invention excluding the oscillatory drive mechanism;
Figures 2A to 2D illustrate the sequential operation of the valve mechanism illustrated in figure 1 including the oscillatory drive mechanism;
Figure 3 A and 3B illustrates the means of moving the pivot of the valve drive mechanism illustrated in figures 2A to 2D to provide a variable valve lift and duration;
Figure 4 is a plot of valve lift against drive shaft angle for varying control angles for a typical variable valve mechanism as illustrated in figures 2 and 5 ;
Figures 5A to 5D illustrate the sequential operation of the valve mechanism with a drive shaft in the position illustrated in figure 3;
Figure 6A to 6D shows a method of mounting the valve to the mechanism to provide the limited axial and pivotal motion kinematically required;
Figure 7 illustrates an alternative valve mechanism in accordance with the present invention;
The valve mechanism illustrated in figures 1A to IE comprise a poppet valve 11 with valve stem 12 and valve head 13. The valve stem 12 is slidingly located in a valve guide 14 and the valve head 13 is arranged to engage against a valve seat 15, to close port 16. A valve lever 20 is mounted adjacent one end. on pivot 21. A ball formation 22 on the end of valve stem 12 engages in a cylindrical hole 23 in
the end of valve lever 20 remote from pivot 21, so as to permit limited pivotal and axial movement between the valve stem 12 and valve lever 20. A light spring (not shown) acts on the valve lever 20 to take up the limited axial movement between lever 20 and valve stem 12 and ensure that the valve 11 is seated when in the closed position.
A track 25 is provided on the valve lever 20, the lever 20 being bifurcated with upper and lower limbs 26 and 27 which define a straight portion of the track 25. The upper limb 26 is extended, the lower edge of the extended portion defining a circular portion 28 of track 25.
An intermediate lever 30 is mounted on pivot 31, the axis of which coincides with the centre of curvature of the circular portion 28 of track 25, when the valve 11 is seated A drive link 35 is connected at one end to an intermediate lever 30, by means of pivot 36 which is spaced from the pivot 31, and at the other end to rocking link 37 on pivot 33. The rocking lever 37 is connected to coupler 7 by pivot 8 and coupler 8 is attached to conrod 3 by pivot 6. The geometry of the arrangement provides that the phase of the motion of the rocking link 37 is substantially 90 out of phase with the motion of piston 5 attached to conrod 3. A drive pin assembly 40 is provided on the intermediate lever 30.
The drive pin assembly 40 comprises control engage solenoid 92 to move retractable pin 39 into engagement with track 25 and control disengage solenoid 91 to remove retractable pin 39 from engagement with track 25. Latch solenoid 90 is energised when the control disengage solenoid 91 disengages retractable pin 39 from track 25 to hold lever 20 and thus valve 11 in the closed position.
The engine comprises a drive shaft I connected to a crank 2 which drives a conrod 3 which is attached to a piston 5 via a gudgen pin 4. The piston 5 reciprocates in a cylinder 10. The rocking link 37 is driven from the main crank shaft of the engine via coupling link 7 attached to pivot 6 on the conrod 3.
When the drive shaft 1 is rotated, the motion of the crank 2 is transmitted via the conrod 3 to link 7 which is attached by pivot 8 to cause rocking link 37 to oscillate about pivot 33. The motion of rocking link 37 is transmitted by drive link 35 through pivot 38, which causes the intermediate lever 30 to oscillate about pivot 31, and drive pin assembly 40 to move forwards and backwards along track 25.
Starting from a position illustrated in figure 2A, the retractable pin 39 will initially engage the lower limb 27 defining the straight portion of the track 25, whereafter further movement of the intermediate lever 30 will cause downward movement of the valve lever 20. thus opening valve 11. This continues
until the position illustrated in figure 2B where the valve will be fully opened Continued rotation of the drive shaft 1 will then cause drive pin 39 to engage the straight portion of limb 26 of lever 20, thus pivotting valve lever 20 upwardly until at the end of the straight portion of limb 26, the valve 11 will be closed as illustrated in figure 2C. Continued rotation of the drive shaft 1 will drive pin 39 to move round the circular portion 28 of track 25, the retractable pin 39 moving about the same axis as the centre of curvature of the circular portion 28, the valve lever 20 remaining in the position illustrated in figure 2D and the valve 11 remaining closed. The retractable pin 39 will then continue to slide against the circular surface of limb 26 the valve remaining shut. Whilst the retractable pin 39 is sliding against the circular surface of limb 26 the retractable pin 39 is retracted, by operating control disengage solenoid 91, for the following complete revolution of the drive shaft 1. The valve 11 remains motionless for this period. At the end of this complete revolution of the drive shaft 1 the retractable pin 39 is extended into engagement by the control engage solenoid 92, whilst the drive pin assembly 40 is in close proximity to the circular surface of limb 26.
With the valve mechanism described above, the valve timing and lift are fixed This is acceptable for operation of the exhaust valves of an engine and, as a compromise, for inlet valves. However, modem high performance internal combustion engines have been developed to give maximum power and output at high engine speeds. In order to achieve this, the valve mechanism is required to give high lift with long duration to encourage gas flow at high speeds. In such high performance engines, the gas flow at low engine speeds is very much compromised. Under such conditions, incoming air is spilled back into the manifold due to late closing of the inlet valve, producing a corresponding reduction in torque output available at low speeds. Also, the exhaust gas is released too early, reducing the expansion ratio of the engine and hence its efficiency. Furthermore, the overlap period where both inlet and exhaust valves are open is too large and allows free flow of air and fuel through the exhaust valve, thus causing emission problems.
The lift and timing of the valve mechanism described above depends on the portion of the track 25 that is engaged by the retractable pin 39. This may be adjusted by adjusting the position of the pivot 33. As illustrated in figure 3, the control shaft 41 is mounted for rotation within the engine block in suitable bearings. The pivot point 33 is in turn mounted eccentrically on shaft 41. The shaft 41 is rotated by lever arm 42 attached by pivot 43 to control link 44. As the pivot 33 is mounted eccentrically of shaft 41, rotation of the shaft 41 will alter the separation between the pivot 38 and the pivot 31 of intermediate lever 30 and hence the portion of track 25 which is engaged by retractable pin 39.
As the shaft 41 is rotated to vary the position of the pivot 33, relative movement will also vary the position of maximum opening relative to the position of the crank shaft of the engine, in addition to varying the lift and duration of opening of the valve.
The position of the drive arrangement illustrated in figure 3A corresponds to the position of the valve mechanism illustrated in figure I and as the drive shaft 1 is rotated, the valve mechanism will operate as described above with reference to figures 2A to 2D. In this set up, the control angle, that is the angle subtended between the line connecting the centre of pivot 43 and the centre of shaft 41 and the horizontal is 00. At high engine speeds, shaft 41 may be rotated so that the control angle is increased to say 300, as illustrated in figure 3B.
With the control angle at 300, upon rotation of shaft 1, the valve mechanism will effect the sequential operation illustrated in figures 5A to 5D. As illustrated in the figures 5A to 5D, the angular displacement of the drive shaft lover which the valve 11 is open, that is between the positions illustrated in figures 5A to 5C, is very much increased, as is the maximum lift of the valve 11 as illustrated in figure 5B.
The means for rotating shaft 41 may be controlled in accordance with, for example engine speed, to give a progressive increase in the control angle as the engine speed increases. As illustrated in figure 4, this will produce a progressive increase in duration of valve opening when measured in degrees of rotation of the drive shaft, and valve lift and will also produce an advance in the point at which the maximum valve opening occurs. Operation of the valve mechanism can consequently be matched to the engine requirements over a wide range of engine speeds. Rotation of the shaft 41 may alternatively be used to control the power output of the engine by controlling the inlet valve to vary the amount of air or air/fuel mixture which is drawn into the engine. The means for rotation of shaft 41 may consequently be controlled by the throttle mechanism or some other engine management system.
In multi-valve arrangements a plurality of valves may be similarly driven from their respective conrods 3. With a variable valve arrangement, the control shaft 41 may be interconnected for adjustment purposes.
The motion of the drive mechanism might be adapted for exhaust and inlet valves on the same cylinder so that only a single attachment need be made to the crank for each cylinder. The link 37 could be provided with two pivots 38 to drive separate links 35 for both inlet and exhaust. Careful choice of dimensions and geometry could provide both inlet and exhaust valves with an acceptable variation in lift and duration for movement of the control pivot 33
For engines with two or more inlet or exhaust valves a common link 30 might drive individual valve levers 20 attached to valves 11 For engines with two adjacent cylinders in which the pistons move in phase a single valve train mechanism might be used driving to individual levers 20 attached to the valves. For a four stroke cycle the retractable drive pin 39 would engage in alternate cylinder valve levers on alternate rotations of the drive shaft 1. Thus a twin cylinder four stroke engine would require a single linkage mechanism to control the inlet and exhaust valves on two cylinders, each cylinder filing alternately.
The valve attachment arrangement illustrated in figure 6A to 6D depicts a method of achieving a coupling between the rotational motion of the valve lever 20 and the valve 11. The block 101 is attached to the valve lever 20 such that the axis of the cylinder intersects with the pivot axis of the valve lever. This condition ensures that there are no resolved axial forces, other than frictional forces, along the axis of the block The upper 102 and lower slippers 103 are formed to cylindrical surface corresponding to the diameter of the hole in the block 101. Both upper 102 and lower slippers 103 have a part spherical cavity, the centre of which coincides with the axis of the cylindrical surface of the slippers 102 and 103. The ball end 22 of the valve 11 has a radius equal the radius of the part spherical cavity. The lower slipper 102 has a clearance hole to allow small angular movement between the valve stem 12 and the lower slipper 102. The block 101 could be an integral part of the lever 20.
In the embodiment illustrated in Figure 7, the drive pin assembly 60 is driven in linear reciprocating manner by means of rod 61. The track 25 in valve lever 20 has a straight portion 62 towards the end of the lever 20 which engages the valve 11, this straight portion being aligned with the path of drive pin assembly 60 when the valve 11 is closed ; and a curved portion 63 towards the pivot 21 end of lever 20, which when engaged by the retractable drive pin 65 will cause the lever 20 to pivot, opening the valve
11. The construction and action of the drive pin assembly is similar to the drive pin assembly 40 described with reference to figure 1.
The rod 60 may be driven in any suitable manner which will provide positive drive in both directions, for example a crank and connecting rod or Scotch yoke mechanism. The mean position of oscillation of drive pin assembly 60 may also be varied by suitable means, for example by variation of the position of the drive linkage in similar manner to that described with reference to Figure 1 or variation of the length of rod 61.
Various modifications may be made without departing from the invention. For example, it will be appreciated that while in the embodiment illustrated in Figure 1, the retractable drive pin position is controlled by means of solenoids the position of the retractable drive pin might also be controlled mechanically using the motion of the link 30 to switch alternatively between positions. Also, the derived motion for the linkage has been described as an attachment to the conrod 3 this could equally be directly pivotally attached to the crankshaft or to a second shaft driven at the same speed as the crank
Claims (24)
1. A valve mechanism comprising ; a valve having a valve stem which is located for axial movement in a valve guide and a valve head adapted at one extreme of movement of the valve to locate against and close a valve seat; characterised in that a valve lever (20) is pivotally mounted at one end (21) and attached adjacent the other end (23) to the end (22) of the valve stem (12) remote from the valve head (13); said valve lever (20) defining a track (25) ; a drive pin assembly (40; 60) consisting of a retractable pin (39; 65) mounted within a housing, having a first position which is engaged with, and a second position which is disengaged with said track with control means to move between said first and second positions and drive means (30,35 ; 61) to drive said drive pin assembly (40; 60) in oscillatory manner, said track (25) having a first portion (28,62) which, when the valve (11) is closed and the retractable pin 39 is in said first position, coincides with the path of the retractable pin (39; 65) and a second portion (26,27 ; 63) which diverges from the path of the retractable pin (39; 65), so that engagement of the second portion (26,27 ; 63) by the retractable pin (39 ; 61) will cause the valve lever (20) to move opening and closing the valve (11).
2. A valve mechanism according to Claim 1 characterised in that on a multi cylinder engine the retractable pin (39 ; 65) is disengaged on some cylinders on demand to provide cylinder disablement.
3 A valve mechanism according to Claim 1 characterised in that the retractable pin (39; 65) engages and disengages with the track (25) on alternate cycles of the drive shaft (1).
4 A valve mechanism according to Claim 1 or 3 characterised in that the frequency of the oscillatory motion of the drive pin assembly (40 ; 60) is equal to the frequency of the drive shaft (1)
5 A valve mechanism according to Claim I characterised in that the retractable pin (39) oscillates in an arcuate path.
6. A valve mechanism according to Claim 1,3, 4, or 5 characterised in that the retractable pin (39) is provided on an intermediate lever (30), said intermediate lever (30) being pivotally mounted for rotation about an axis parallel to the axis of rotation of the valve lever (20); a drive link (35) is pivotally connected at one end to the intermediate lever (30) and at the other end to a rocking link
(37) on a pivot (33). further connected by linkage (7, 3) to the drive shaft (1), so that upon rotation of the drive shaft (1) the intermediate lever (30) and drive pin (39) thereon will oscillate about its pivot (31) ; the first portion (28) of the track (25) on the valve lever (20) being arcuate having a radius equal to the separation between the pivot (31) of the intermediate lever (30) and the retractable pin (39) thereon.
7.. A valve mechanism according to Claim 6 characterised in that the second portion (26,27) of the track (25) is straight and joined tangentially to the arcuate track 25.
8. A valve mechanism according to Claim 7 characterised in that the valve lever (20) is bifurcated having parallel limbs (26,27) which define therebetween the straight second portion of the track (25), the upper limb (26) being extended, the lower edge of the extended portion defining the circular first portion (28) of the track (25).
9. A valve mechanism according to Claim I characterised in that the drive pin assembly (60) is driven in linear reciprocating manner.
10. A valve mechanism according to Claim 9 characterised in that the first portion (62) of the track (25) is disposed towards the end of the valve lever (20) connected to the valve stem (12) and is straight while the second portion (63) of the track (25) is curved.
11. A valve mechanism according to Claim 1 or 8 characterised in that means (41) is provided for varying the mean position of oscillation of the retractable pin (39 ; 65).
12. A valve mechanism according to Claim 11 characterised in that the retractable pin (39) is driven by an intermediate pivotted lever (30), from a link (35) from a rocking link (37) connected via a coupler to the drive shaft (1) means (41) being provided for varying the separation between the pivot connection (33) on the rocking link (37) and the pivotal axis of the intermediate lever (30).
13. A valve mechanism according to Claim 12 characterised in that the adjustment shaft (41) is mounted in a bearing with rocking lever (37) pivot (33) formed eccentrically on adjustment shaft (41) such that upon rotation of the shaft (41), separation between the axis of the rocking lever pivot (33) and the pivotal axis of the intermediate lever (30) will be adjusted, means being provided for rotation of the adjustment shaft (41).
14. A valve mechanism according to any one of Claims 11 to 13 characterised in that the means (41) for varying the mean position of oscillation of the retractable pin (39 ; 81) is controlled as a function of the engine speed.
15. A valve mechanism according to any one of Claims 11 to 13 characterised in that the means (41) for varying the mean position of oscillation of the retractable pin (39; 65) is controlled to control the power output of the engine.
16. A valve mechanism according to any one of the preceding claims characterised in that the valve stem (12) is attached to the valve lever (20) in a manner which will permit limited pivotal and axial movement therebetween.
17. A valve mechanism according to Claim 16 characterised in that a ball (22) on the end of the valve stem (12) engages in a spherical seat between two part cylindrical slippers located in cylindrical hole (23) in the end of the valve lever (20).
18. A valve mechanism according to Claim 16 or 17 characterised in that resilient means (24) acts on the valve lever (20) in order to ensure that the valve (11) is seated when in its closed position.
19. A valve mechanism according to Claim 16 or 17 characterised in that means is provided to hold the position of the valve lever (20) when the retractable pin (39,65) is disengaged.
20. A valve mechanism according to Claim 19 characterised in that the holding means is an electrical solenoid.
21. A valve mechanism according to any preceding Claim characterised in that both exhaust and inlet valve levers 20 are driven from the same rocking link (37).
22. A valve mechanism according to any preceding Claim characterised in that multi inlet or exhaust valves for one engine cylinder are driven from same intermediate link (30).
23. A valve mechanism according to any preceding Claim characterised in that in an engine with adjacent cylinders in which the pistons are in phase but in which firing is alternate, can be driven from the same intermediate link (30) with the retractable pin (39) alternately engaging the valve levers (20) of the adjacent cylinders.
24. A multi-valve assembly comprising a plurality of valve mechanisms as claimed in any one of
Claims 1 to 23, characterised in that the valve mechanisms have a common adjustment shaft (41).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB0029048A GB2372071A (en) | 2000-11-29 | 2000-11-29 | Desmodromic valve mechanism |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB0029048A GB2372071A (en) | 2000-11-29 | 2000-11-29 | Desmodromic valve mechanism |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB0029048D0 GB0029048D0 (en) | 2001-01-10 |
| GB2372071A true GB2372071A (en) | 2002-08-14 |
Family
ID=9904065
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB0029048A Withdrawn GB2372071A (en) | 2000-11-29 | 2000-11-29 | Desmodromic valve mechanism |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2372071A (en) |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4576128A (en) * | 1983-12-17 | 1986-03-18 | Honda Giken Kogyo Kabushiki Kaisha | Valve operation stopping means for multi-cylinder engine |
| EP0311282A2 (en) * | 1987-10-03 | 1989-04-12 | Jaguar Cars Limited | Valve mechanisms |
| EP0416794A1 (en) * | 1989-09-08 | 1991-03-13 | Jaguar Cars Limited | Valve mechanisms |
| WO1998036157A1 (en) * | 1997-02-13 | 1998-08-20 | Headstrong Design Pty Ltd | Adjustment mechanism for valves |
| WO2001029466A1 (en) * | 1999-10-15 | 2001-04-26 | Vee Two Pty Ltd. | A guide plate for a poppet valve |
| US20010037781A1 (en) * | 2000-01-26 | 2001-11-08 | Fischer Thomas H. | Variable valve mechanism having an eccentric-driven frame |
-
2000
- 2000-11-29 GB GB0029048A patent/GB2372071A/en not_active Withdrawn
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4576128A (en) * | 1983-12-17 | 1986-03-18 | Honda Giken Kogyo Kabushiki Kaisha | Valve operation stopping means for multi-cylinder engine |
| EP0311282A2 (en) * | 1987-10-03 | 1989-04-12 | Jaguar Cars Limited | Valve mechanisms |
| EP0416794A1 (en) * | 1989-09-08 | 1991-03-13 | Jaguar Cars Limited | Valve mechanisms |
| WO1998036157A1 (en) * | 1997-02-13 | 1998-08-20 | Headstrong Design Pty Ltd | Adjustment mechanism for valves |
| WO2001029466A1 (en) * | 1999-10-15 | 2001-04-26 | Vee Two Pty Ltd. | A guide plate for a poppet valve |
| US20010037781A1 (en) * | 2000-01-26 | 2001-11-08 | Fischer Thomas H. | Variable valve mechanism having an eccentric-driven frame |
Also Published As
| Publication number | Publication date |
|---|---|
| GB0029048D0 (en) | 2001-01-10 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| 9110 | Period prescribed has been extended under rule 110(6)/1990 |
Free format text: EXTENSION ALLOWED: PERIOD(S) PRESCRIBED BY RULE(S) 33(2) EXTENDED UNDER RULE 110(6) IN ACCORDANCE WITH THE DECISION OF THE COMPTROLLER DATED 20030423. |
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| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |