GB2280050A - Voltage regulator for a hand-held appliance - Google Patents
Voltage regulator for a hand-held appliance Download PDFInfo
- Publication number
- GB2280050A GB2280050A GB9318758A GB9318758A GB2280050A GB 2280050 A GB2280050 A GB 2280050A GB 9318758 A GB9318758 A GB 9318758A GB 9318758 A GB9318758 A GB 9318758A GB 2280050 A GB2280050 A GB 2280050A
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- GB
- United Kingdom
- Prior art keywords
- transistor
- resistor
- voltage regulator
- source
- drain
- 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.)
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Classifications
-
- G—PHYSICS
- G05—CONTROLLING; REGULATING
- G05F—SYSTEMS FOR REGULATING ELECTRIC OR MAGNETIC VARIABLES
- G05F3/00—Non-retroactive systems for regulating electric variables by using an uncontrolled element, or an uncontrolled combination of elements, such element or such combination having self-regulating properties
- G05F3/02—Regulating voltage or current
- G05F3/08—Regulating voltage or current wherein the variable is dc
- G05F3/10—Regulating voltage or current wherein the variable is dc using uncontrolled devices with non-linear characteristics
- G05F3/16—Regulating voltage or current wherein the variable is dc using uncontrolled devices with non-linear characteristics being semiconductor devices
- G05F3/20—Regulating voltage or current wherein the variable is dc using uncontrolled devices with non-linear characteristics being semiconductor devices using diode- transistor combinations
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- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Nonlinear Science (AREA)
- Electromagnetism (AREA)
- General Physics & Mathematics (AREA)
- Radar, Positioning & Navigation (AREA)
- Automation & Control Theory (AREA)
- Control Of Direct Current Motors (AREA)
Abstract
A hand-held electric appliance, such as a hair-clipper, has a voltage regulator including a transistor Q1 serially connected to a source of full-wave rectified alternating current potential. The transistor Q1 is an enhanced, metal oxide semi-conductor, field-effect transistor that regulates a rectified alternating current potential and outputs a regulated potential to a d.c. motor M. A biasing resistor R1 and zener diode Z1 are connected to the transistor Q1 for biasing the transistor, thereby enabling regulation of the rectified potential. Such a regulator improves the efficiency of the motor, as well as increasing the life of the motor and reducing the size of the required suppression components. A filter circuit L1, C2, R4 reduces radio frequency interference. <IMAGE>
Description
VOLTAGE REGULATOR FOR A HAND-HELD APPLIANCE
BACKGROUND OF THE INVENTION
Technical Field
The invention relates generally to hand-held appliances such as a hand-held hair-clipper. More particularly, the invention relates to a voltage regulator for a hand-held hairclipper.
Related Prior Art
It is generally known to provide hand-held appliances such as a hair-clipper with a low-power electric motor.
It is also known to provide power to an electric motor from an alternating current ("a.c.") source, to reduce the incoming a.c. voltage using a step-down transformer and to convert the a.c. voltage to d.c. voltage.
It is also known to provide power to an electric motor using a silicon controlled rectifier to provide phase controlled a.c. to the motor of a hand-held appliance.
It is also known to provide a series connected, bipolar junction or junction field-effect transistor to regulate an unregulated d.c. voltage source.
Attention is directed to U.S. Patent No. 3,983,473 entitled "Series Direct-Current Voltage Regulator", issued on May 6, 1974, to Sanderson.
Attention is also directed to the following United
States Patents:
2,751,549 3,317,817
3,101,441 3,947,753
3,241,045 3,986,102
3,244,963 4,437,148 SUMMARY OF THE INVENTION
In the case of an appliance that utilizes a low power d.c. motor, and that is to be operated using a voltage greater than 120 volts, e.g. at 220 or 240 volts, 50 hertz, as provided in Europe, some method must be employed to reduce the a.c. source voltage to a d.c. operating voltage compatible with the motor.
In the case of a hand-held electrical appliance, such as a hairclipper, the method of conversion must be small, light, and very efficient. A step-down transformer cannot be used because it cannot be made small enough, due to the great number of turns necessary to reduce the voltage from 220/240 volts a.c. to an appropriate a.c. voltage for rectification and regulation. The transformer could not conveniently fit inside the housing for the hand-held hair-clipper without resulting in a design which is bulky, heavy, and difficult to use.
Alternatively, the use of phase controlled a.c. to operate an electric motor is inefficient and reduces the life of the motor because of the high peak voltages supplied to the motor.
The invention provides in a hand-held electrical appliance, such as a hair-clipper, a voltage regulator for the appliance, which regulator comprises transistor means adapted to be connected to a source of alternating current potential and including a series connected transistor for regulating the alternating current potential and outputing a regulated potential, and biasing means connected to the transistor means for biasing the transistor to enable regulation of the rectified potential.
The invention also provides in a hand-held electric appliance, such as a hair-clipper, a voltage regulator for the appliance, which regulator comprises a hot input terminal and a negative input terminal for inputing an alternating current potential, filter means connected to the input terminals for reducing radio frequency interference ("RFI") in the voltage regulator, rectifying means connected to the filter means for rectifying the alternating current potential and outputing a rectified potential, transistor means connected to the rectifying means for regulating the rectified potential and outputing a regulated potential, and biasing means connected to the transistor means for biasing the transistor to allow regulation of the rectified potential.
The invention also provides in a hand-held electric appliance, such as a hair-clipper, a voltage regulator for the appliance, which regulator comprises a hot input lead and a neutral input lead, a switch connected to one of the leads, a capacitor connected between the leads, a first resistor connected to the capacitor and to the switch, an inductor connected in series with the resistor, a full-wave rectifier including four diodes connected to form a full-wave bridge, a pair of input terminals wherein one input terminal is connected to the inductor and the other input terminal is connected to the neutral input lead, a positive output terminal and a negative output terminal, a second resistor connected to the positive output terminal, a third resistor connected to the negative output terminal, a fourth resistor connected to the second resistor, a zener diode having an anode connected to the third resistor and a cathode connected to the fourth resistor, a field-effect transistor having a gate connected to the fourth resistor and to the cathode, a drain connected to the second resistor and to the fourth resistor, a source, and a diode between the drain and the source, the diode including a cathode connected to the drain and an anode connected to the source, and a capacitor connected parallel to the regulator between the source and the zener diode anode.
It is a principal advantage of the invention to provide a voltage regulator for a hand-held appliance that is capable of rectifying and regulating a high voltage input.
It is another advantage of the invention to provide a voltage regulator for a hand-held appliance that is compact and light weight.
It is another advantage of the invention to provide a voltage regulator that improves the efficiency of the motor.
It is another advantage of the invention to provide a voltage regulator that increases the life of the motor.
It is another advantage of the invention to provide a voltage regulator that reduces the RFI in the circuit thereby reducing the size of the required suppression components.
Other features and advantages of the invention will become apparent to those skilled in the art upon review of the following detailed description, claims, and drawings.
DESCRIPTION OF THE DRAWINGS
Figure 1 is a circuit schematic of the voltage regulator and motor of the hair-clipper embodying the invention.
Figure 2a is a view of a typical alternating current input waveform seen at input terminals of the circuit embodying the invention.
Figure 2b is a view of the full-wave rectified voltage output of rectifier B1.
Figure 2c is a view of the regulated output voltage of transistor Q1 without smoothing capacitor C1 in the circuit.
Figure 2d is a view of the regulated output voltage of transistor Q1 with smoothing capacitor C1 added to the circuit.
Figure 3 is a side elevational view of the hair-clipper embodying the invention.
Before one embodiment of the invention is explained in detail, it is to be understood that the invention is not limited in its application to the details of the construction and the arrangements of components set forth in the following description or illustrated in the drawings. The invention is capable of other embodiments and of being practiced or being carried out in various ways. Also, it is to be understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
Shown in Figure 3 of the drawings is a hair-clipper 2 embodying the invention. The hair-clipper 2 includes a two-piece housing 4 having mounted thereon a fixed blade 6. As is known in the art, a reciprocating blade 8 is also provided for reciprocation relative to the fixed blade 6. The relative movement between the blades, 6 and 8, provides the cutting action of the hair-clipper 2. The hair-clipper 2 includes a low power rotary, d.c. electric motor 10 mounted in the housing 4. The particular details of the motor 10 form no part of the invention.
Accordingly, and for the sake of brevity, the motor 10 will only be briefly described.
As is known in the art, the motor 10 includes a motor housing 11 and an arbor or rotating shaft 12 supported by the motor housing 11 for rotation about an axis (not shown). The rotating shaft 12 is mechanically connected, using appropriate means, to the reciprocating blade 8 on the hair-clipper 2 to cause movement of the blade 8.
The motor 10 also includes an armature (not shown) connected to the rotating shaft 12. The armature includes armature windings for generating an armature field. Electricity is transferred to the armature via a pair of commutator brushes in a manner that is also well known in the art.
As is also known in the art, the motor 10 also includes a stator assembly (also not shown) which generates a magnetic field thereby rotating the armature and rotating shaft assembly within the housing 11.
Figure 1 of the drawings schematically illustrates the electronic components of a hair-clipper 2 embodying the invention. As shown, the hair-clipper 2 includes a voltage regulator for supplying power to the electric motor 10. The voltage regulator includes an electrolytic capacitor C1 connected in parallel to the motor. The capacitor C1 includes a positive lead 14 and a negative lead 18 each of which is electrically connected to a respective motor commutator brush using appropriate means.
The voltage regulator also includes transistor means for regulating a pulsating waveform and outputing a regulated, d.c. potential to the motor 10. In the preferred form of the invention, the transistor means comprises an integrated circuit 22 forming an enhanced or enhancement mode, metal oxide semiconductor, field-effect transistor Q1. Though other types of transistors may be used, the transistor Q1 must be of a type capable of dissipating high energy resulting from a high voltage input. The transistor Q1 includes a source terminal 26 connected to the positive terminal 14 of the electrolytic capacitor C1.
The transistor Q1 also includes a drain terminal 30 and a gate terminal 34.
The integrated circuit 22 also includes a diode D1 having a cathode 38 and an anode 42. The diode D1 is connected between the drain and source terminals, 30 and 26, of the transistor Q1. The cathode 38 is connected to the drain 30 and the anode is connected to the source 26.
The voltage regulator also includes biasing means for biasing the transistor Q1 thereby enabling operation of the transistor Q1 and regulation of a rectified potential. In the embodiment shown in the drawings, the biasing means includes a zener diode Z1 having a cathode 46 connected to the gate terminal 34 of the transistor Q1 and an anode 50 connected to the negative terminal 18 of the electrolytic capacitor C1. The biasing means also includes a biasing resistor R1 connected between the drain 30 and the gate 34 of the transistor Q1.
The voltage regulator also includes first current limiting means. The first current limiting means comprises a pair of current limiting resistors R2 and R3. One lead of resistor R2 is connected between the drain 30 and resistor R1, while one lead of resistor R3 is connected to the anode 50 of the zener diode Z1.
The voltage regulator also includes rectifying means for rectifying an a.c. potential and outputing a full-wave rectified a.c. potential (also called pulsating d.c. potential) to the current limiting resistors R2 and R3. In the preferred form of the invention, the rectifying means includes four diodes
D2, D3, D4, and D5, connected to form a conventional full-wave bridge B1. The full-wave bridge B1 includes a pair of output terminals 54 each connected to a respective opposite lead of the current limiting resistors R2 and R3 and a pair of input terminals 58.
The voltage regulator also includes filter means connected to the full-wave bridge input terminals 58. The filter means reduces the RFI in the circuit and includes an inductor L1 connected to one of the rectifier input leads 58, a capacitor C2 connected to the other of the rectifier input leads 58, and impedance means connected between the inductor L1 and the capacitor C2. The impedance means limits the inrush current and, in the preferred form of the invention, comprises a resistor R4.
As can be seen from the drawings, capacitor C2, resistor R4 and inductor L1 are connected parallel to the full-wave bridge rectifier B1.
The voltage regulator also includes a switch S1 having a contact terminal 62 connected between resistor R4 and the one side of capacitor C2. The switch S1 also includes a wiper terminal 66 having a switch wiper 70. The wiper terminal 66 is connected to a first or "hot" input terminal or lead 74. A second or "neutral" input terminal or lead 78 is connected to the other side of the capacitor C2. Together, input leads 74 and 78 form a means for inputing electrical power from the source or input voltage (not shown) so that the input voltage is connected parallel to the combination of switch Si and capacitor C2.
In operation, alternating current from a high voltage source (not shown but depicted in Figure 2a, and typically 220/240 V, 50 hz) is connected to input leads 74 and 78. When the switch S1 is closed, current flows to the regulating circuit.
Specifically, current flows through the switch S1 to the RFI filter comprising capacitor C2 and inductor L1. The filter eliminates components of the signal in the radio frequency bandwidths. Resistor R4 is a current limiting component that reduces the current inrush to the circuit. The current flows from the filter to the inputs 58 of the full-wave bridge rectifier B1.
The rectifying bridge B1 produces the full-wave rectified a.c. potential or pulsating d.c. potential (shown in
Figure 2b) at the rectifier outputs 54. The full-wave rectified current flows through current limiting resistor R2 and biasing resistor R1 to the zener diode Z1. The current causes the zener diode Z1 to establish and maintain a reference voltage at the gate terminal 34 of the transistor Q1 thereby setting a positive gate-to-source voltage.
The full-wave rectified a.c. signal is also received at the drain 30 of the transistor Q1. If the gate-to-source voltage is greater than the threshold voltage of the transistor Q1, the transistor conducts and provides an output voltage to the hairclipper motor 10 (in accordance with the transistor operating characteristics) which is suitable for operating the low powered d.c. motor 10. Diode D1 prevents the transistor Q1 from entering the breakdown operating region when the voltage at the drain drops below a threshold level during each cycle of the input.
Figure 2c shows the output voltage waveform that would be generated by the transistor Q1 if smoothing capacitor C1 were not provided. The ripple voltage of the signal shown in Figure 2c is a result of having a load on the circuit during the periods when the input voltage drops below the threshold voltage. The addition of the capacitor C1 results in an output waveform (shown in Figure 2d) which has a much reduced ripple voltage resulting from variations of the input voltage. The size of the ripple voltage generated with capacitor C1 in the circuit will also vary depending upon the characteristics of the particular capacitor employed.
Various features of the invention are set forth in the following claims.
Claims (12)
1. In a hand-held electrical appliance, such as a hair-clipper, a voltage regulator for said appliance, said regulator comprising transistor means adapted to be connected to a source of alternating current potential and including a series connected transistor for regulating the alternating current potential and outputing a regulated potential, and biasing means connected to said transistor means for biasing said transistor to enable regulation of the rectified potential.
2. A voltage regulator as set forth in Claim 1 wherein said transistor comprises a gate, a drain, and a source, and wherein said biasing means comprises impedance means connecting said drain to said gate and further comprises a zener diode having a cathode connected to said gate to provide a reference voltage for said transistor.
3. A voltage regulator as set forth in Claim 2 wherein said regulator further comprises a hot input terminal and a neutral input terminal for inputing an alternating current potential, filter means connected to said input terminals for reducing radio frequency interference ("RFI") in said voltage regulator, and rectifying means connected to said filter means for rectifying the alternating current potential and outputing a full-wave rectified potential to said transistor means.
4. A voltage regulator as set forth in Claim 3 wherein said RFI reducing means comprises a capacitor connected between said input terminals, impedance means connected to said hot input terminal and to said capacitor for limiting current, and an inductor connected in series with said impedance means between said impedance means and said rectifying means.
5. A voltage regulator as set forth in Claim 4 and further comprising a capacitor having positive and negative leads, and wherein said positive lead is connected to said source and said negative lead is connected to said anode.
6. A voltage regulator as set forth in Claim 5 and further comprising a diode having a cathode connected to said drain and an anode connected to said source.
7. In a hand-held electric appliance, such as a hairclipper, a voltage regulator for said appliance, said regulator comprising a hot input terminal and a neutral input terminal, said input terminal for inputing an alternating current potential, filter means connected to said input terminals for reducing radio frequency interference ("RFI") in said voltage regulator, rectifying means connected to said filter means for rectifying the alternating current potential and outputing a rectified potential, transistor means connected to said rectifying means for regulating the rectified potential and outputing a regulated potential, and biasing means connected to said transistor means for biasing said transistor to allow regulation of the rectified potential.
8. A voltage regulator as set forth in Claim 7 wherein said transistor means comprises an enhanced metal oxide semiconductor field-effect transistor having a gate, a drain and a source, and wherein said biasing means comprises impedance means connecting said drain to said gate and a zener diode having a cathode connected to said gate to provide a reference voltage for said transistor.
9. A voltage regulator as set forth in Claim 8 wherein said RFI reducing means comprises a capacitor connected between said input terminals, impedance means connected to said hot input terminal and to said capacitor for limiting current inrush, and an inductor connected in series with said impedance means between said impedance means and said rectifying means.
10. A voltage regulator as set forth in Claim 9 and further comprising a capacitor having positive and negative leads, and wherein said positive lead is connected to said source and said negative lead is connected to said anode.
11. A voltage regulator as set forth in Claim 10 and further comprising a diode having a cathode connected to said drain and an anode connected to said source.
12. A hand-held electrical appliance such as a hairclipper, the appliance comprising:
a housing of a size adapted to be held in a user's hand;
a motor supported by said housing; and
a voltage regulator for said appliance, said regulator supplying power to drive said motor and comprising a hot input lead and a neutral input lead, a switch connected to one of said leads, a capacitor connected between said leads, a first resistor connected to said capacitor and to said switch, an inductor connected in series with said resistor, a full-wave rectifier including four diodes connected to form a full-wave bridge, a pair of input terminals wherein one input terminal is connected to said inductor and the other input terminal is connected to said neutral input lead, a positive output terminal and a negative output terminal, a second resistor connected to said positive output terminal, a third resistor connected to said negative output terminal, a fourth resistor connected to said second resistor, a zener diode having an anode connected to said third resistor and a cathode connected to said fourth resistor, a field-effect transistor having a gate connected to said fourth resistor and to said cathode, a drain connected to said second resistor and to said fourth resistor, a source, and a diode having a cathode connected to said drain and an anode connected to said source, and a further capacitor connected parallel to said regulator between said source and said zener diode anode.
12. In a hand-held electric appliance, such as a hairclipper, a voltage regulator for said appliance, said regulator comprising a hot input lead and a neutral input lead, a switch connected to one of said leads, a capacitor connected between said leads, a first resistor connected to said capacitor and to said switch, an inductor connected in series with said resistor, a full-wave rectifier including four diodes connected to form a full-wave bridge, a pair of input terminals wherein one input terminal is connected to said inductor and the other input terminal is connected to said neutral input lead, a positive output terminal and a negative output terminal, a second resistor connected to said positive output terminal, a third resistor connected to said negative output terminal, a fourth resistor connected to said second resistor, a zener diode having an anode connected to said third resistor and a cathode connected to said fourth resistor, a field-effect transistor having a gate connected to said fourth resistor and to said cathode, a drain connected to said second resistor and to said fourth resistor, a source, and a diode between said drain and said source, said diode including a cathode connected to said drain and an anode connected to said source, and a capacitor connected parallel to said regulator between said source and said zener diode anode.
13. The voltage regulator as set forth in Claim 12
wherein said field-effect transistor comprises an enhanced metal
oxide semiconductor field effect transistor.
14. A voltage regulator for a hand-held electrical appliance substantially as hereinbefore described with reference to the accompanying drawings.
Amendments to the claims have been filed as follows 1. A hand-held electrical appliance such as a hairclipper, the appliance comprising:
a housing of a size adapted to be held in a user's hand;
a motor supported by said housing; and
a voltage regulator for supplying power to drive said motor and comprising transistor means adapted to be connected to a source of alternating current potential and including a series connected transistor for regulating the alternating current potential and outputting a regulated potential, and biasing means connected to said transistor means for biasing said transistor to enable regulation of the alternating current potential.
2. A voltage regulator as set forth in claim 1, wherein said transistor comprises a gate, a drain, and a source, and wherein said biasing means comprises impedance means connecting said drain to said gate and further comprises a zener diode having a cathode connected to said gate to provide a reference voltage for said transistor.
7. A hand-held electrical appliance such as a hairclipper, the appliance comprising:
a housing of a size adapted to be held in a user's hand;
a motor supported by said housing; and
a voltage regulator for said appliance, said regulator supplying power to drive said motor and comprising a hot input terminal and a neutral input terminal for inputting an alternating current potential, filter means connected to said input terminals for reducing radio frequency interference ("RFI") in said voltage regulator, rectifying means connected to said filter means for rectifying the alternating current potential and outputting a rectified potential, transistor means connected to said rectifying means for regulating the rectified potential and outputting a regulated potential, and biasing means connected to said transistor means for biasing said transistor to allow regulation of the rectified potential.
8. A voltage regulator as set forth in claim 7, wherein said transistor means comprises an enhanced metal oxide semiconductor field-effect transistor having a gate, a drain and a source, and wherein said biasing means comprises impedance means connecting said drain to said gate and a zener diode having a cathode connected to said gate to provide a reference voltage for said transistor.
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US9270493A | 1993-07-16 | 1993-07-16 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| GB9318758D0 GB9318758D0 (en) | 1993-10-27 |
| GB2280050A true GB2280050A (en) | 1995-01-18 |
Family
ID=22234658
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| GB9318758A Withdrawn GB2280050A (en) | 1993-07-16 | 1993-09-10 | Voltage regulator for a hand-held appliance |
Country Status (1)
| Country | Link |
|---|---|
| GB (1) | GB2280050A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2906417A1 (en) * | 2006-09-22 | 2008-03-28 | Jean Jacques Bigou | Electronic assembly for e.g. electronic equipment, has direct current to direct current converter block containing transformer/insulator whose thickness is reduced by low rate of voltage reduction and high frequency of operation |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1386498A (en) * | 1971-08-04 | 1975-03-05 | Cit Alcatel | Circuit providing a substantially constant output voltage for a varying input voltage |
| US3947752A (en) * | 1974-06-04 | 1976-03-30 | Motorola, Inc. | Circuit for converting alternating current voltages to a constant magnitude direct current voltage |
| US4806844A (en) * | 1988-06-17 | 1989-02-21 | General Electric Company | Circuit for providing on-chip DC power supply in an integrated circuit |
| GB2208980A (en) * | 1987-08-21 | 1989-04-19 | Transtar Limited | Power supply for fluorescent lamp |
| GB2238635A (en) * | 1989-11-27 | 1991-06-05 | Uniqey | A regulated power supply |
-
1993
- 1993-09-10 GB GB9318758A patent/GB2280050A/en not_active Withdrawn
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB1386498A (en) * | 1971-08-04 | 1975-03-05 | Cit Alcatel | Circuit providing a substantially constant output voltage for a varying input voltage |
| US3947752A (en) * | 1974-06-04 | 1976-03-30 | Motorola, Inc. | Circuit for converting alternating current voltages to a constant magnitude direct current voltage |
| GB2208980A (en) * | 1987-08-21 | 1989-04-19 | Transtar Limited | Power supply for fluorescent lamp |
| US4806844A (en) * | 1988-06-17 | 1989-02-21 | General Electric Company | Circuit for providing on-chip DC power supply in an integrated circuit |
| GB2238635A (en) * | 1989-11-27 | 1991-06-05 | Uniqey | A regulated power supply |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2906417A1 (en) * | 2006-09-22 | 2008-03-28 | Jean Jacques Bigou | Electronic assembly for e.g. electronic equipment, has direct current to direct current converter block containing transformer/insulator whose thickness is reduced by low rate of voltage reduction and high frequency of operation |
Also Published As
| Publication number | Publication date |
|---|---|
| GB9318758D0 (en) | 1993-10-27 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |