JP2002221280A - Drive device for fluid control valve - Google Patents

Abstract

(57) [Problem] To provide a drive device for a fluid control valve, which eliminates the need for a resistor as an extra member, thereby improving energy saving and reducing impact to enhance durability. SOLUTION: A current supplied to an electromagnetic coil which drives opening and closing of a fluid control valve is controlled. In the case of the opening operation, a rated current is applied for, for example, 3 seconds.
The PWM drive of 1 ms and the non-energization of 1 ms is repeated for 3 seconds. An average current of 80% of the rating is applied. Alternatively, a direct current supplied to the electromagnetic coil is supplied with a rated current for 3 seconds in the forward direction (opening operation) and 7 times the rated current in the reverse direction (closing operation).
Energize at 0.7% for 3 seconds. A drive circuit is constituted by a MOS-FET, and a bias current is set to about 0.1 mA.
Alternatively, PWM driving is performed to gradually increase the average current during the opening operation, and the energization ratio is increased by 10% every 0.25 seconds. Finally, the rated current is applied for 0.75 seconds, and the "open operation"
To ensure.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric device powered by a battery or a storage battery, particularly a fuel cell power generation system using several or more solenoid valves, or a latch type for controlling a fluid used in an air conditioner or the like. The present invention relates to a drive device for a fluid control valve that drives and controls an electromagnetic coil of a fluid control valve such as an electromagnetic valve.

[0002]

2. Description of the Related Art Conventionally, Japanese Patent Laid-Open Publication No. Hei 11 (1999) discloses an electromagnetic valve for controlling the supply of fuel to a fuel cell.
No. 54141. In this conventional example, six electromagnetic valves are used as disclosed in FIGS. 1 and 4 of the publication, and the electromagnetic valves have a configuration as shown in FIG.
Further, as described in paragraphs [0027] to [0030] of the publication, in the case of “opening operation”, “ON” is always set,
In the case of the "close operation", the solenoid valve is always controlled to be "OFF".

[0003] Electric equipment such as a fuel cell power generation system includes:
In many cases, DC power is used as power for a control system, and a battery or a storage battery is used as a power source in many cases. In such a case, a latch-type solenoid valve for energy saving is used instead of the ON / OFF-type solenoid valve described in the above publication.

(Prior Art-1) FIG. 13 is a sectional view showing a closed state of a latch-type solenoid valve, and FIG. 14 is a view showing operating characteristics of the solenoid valve at the time of detachment. When a voltage is applied to the electromagnetic coil 101 so as to generate a magnetic flux in the same direction as the magnetic flux of the permanent magnet 1, an attractive force is generated by the magnetic flux synthesized from the magnetic flux of the permanent magnet 1 and the magnetic flux of the electromagnetic coil 101, and the plunger 2 Is attracted to the attraction element 4 against the force of the coil spring 3. As a result, the valve 5 is separated from the valve seat 6 to be in a valve open state. Here, even if the energization to the electromagnetic coil 101 is cut off, the gap is eliminated because the attracting element 4 and the plunger 2 are attracted, and the attracting force by the magnetic flux of the permanent magnet 1 which has become stronger is smaller than the force of the coil spring 3. Is also set stronger,
This position (valve open state) is maintained. In this state, when a voltage is applied to the electromagnetic coil 101 so as to generate a magnetic flux in the opposite direction to the magnetic flux of the permanent magnet 1, an attractive force is generated by the magnetic flux obtained by subtracting the magnetic flux of the permanent magnet 1 and the magnetic flux of the electromagnetic coil 101. However, when the suction force is weaker than the force of the coil spring 3, the plunger 2 is detached from the suction element 4, and the valve is opened.

[0005] Here, description will be given of the time of separation with reference to FIG. When a rated voltage is applied to bring the solenoid valve into the "closed" state, the combined attractive force F3 generated by the reduced magnetic flux
(Applied voltage = rated voltage) is generated, but the combined attractive force due to the reduced magnetic flux acts to attract the plunger 2 made of a magnetic material and the attracting element 4, so that the attractive force F3> The force F1 of the coil spring results in the solenoid valve not being in the "closed" state. FIG. 14 shows that when the applied voltage is in the range of V2 to V1, the combined attractive force ≦ the force F1 of the coil spring,
It indicates that the state is "closed". However, in order to perform a stable "valve closing" operation, it is desirable that the applied voltage is set to V0 and the combined attractive force is set to 0, and the coil spring is separated by the force F1 to perform the "closing" operation.

(Prior Art-2) In Japanese Patent Application Laid-Open No. 9-72633, a latch-type pilot is used as pilot means of a four-way valve for reversing the flow path of a refrigerant of an air conditioner as shown in FIG. Solenoid valves are used. Further, as disclosed in FIG. 3 of the publication, the alternating current is rectified and applied to the electromagnetic coil. However, the applied voltage differs between the cooling mode and the heating mode depending on the presence or absence of the resistor 74. I have.

[0007]

As shown in FIGS. 15 and 16, the latch type solenoid valve of the prior art-1 is "closed".
Since the rated voltage is applied even when the device is operated, an extra resistor R must be provided so that the applied voltage V0 of the electromagnetic coil and the voltage applied to the resistor R become VR (rated voltage-V0). For example, it is configured such that V0: VR = 3: 1. However, the value of the resistor R is a discrete value (E-24 series), and it is difficult to select and determine the optimum V0, so that the number of design steps is increased, and the cost is increased economically. R) requires extra cost, so that it becomes economically expensive, and because the rated power is applied during the “open” operation, the combined force of the force by the magnetic flux of the electromagnetic coil and the force by the magnetic flux of the permanent magnet is extremely large. The impact noise at the time of opening the valve may increase, and the impact may shorten the durability (life) of the structural member. There is a problem in that it consumes power and is against energy saving. Further, the latch type solenoid valve of the prior art-2 also requires a resistance as in the case of the prior art-1.

That is, the prior art-1 and the prior art-2
Therefore, when the solenoid valve is operated to be "closed", an extra resistor R is required to apply the rated voltage, which is economically expensive. Further, in the prior art 1, since the resistor R consumes electric power even for a short time, it is not preferable in the global environment against energy saving. In the prior art-1, the desirable resistance R is determined by the structural requirements of the structure side (fluid control valve). However, it is difficult to select a standard resistor, and even if the rated voltage is applied, it is not sufficient to meet the optimal conditions for the "close" operation. It is expensive. In addition, conventional technology-1
Because the rated voltage is applied to the "open" operation, the combined force of the electromagnetic force may be large, the sound of the impact when opening the valve is large, and the durability (life) of the structural member is extended due to the impact. I couldn't. Further, the prior art-1 is “closed”.
Since an extra resistor R is required for operation, IC
It is impossible to use an H-switch (double arm) which is widely used widely, and space saving cannot be realized.

It is an object of the present invention to provide a drive device that does not require an extra member, ie, a resistance, and to provide a drive device in which impact is reduced and durability (life) of a fluid control valve is increased. To each purpose.

[0010]

According to a first aspect of the present invention, there is provided a driving apparatus for a fluid control valve, wherein an electromagnetic coil constituting a flow path switching valve is driven at a first predetermined current for a predetermined time to be positioned at a first position. In the fluid control valve driving device for holding or holding the electromagnetic coil at a second location by driving the electromagnetic coil at a second predetermined current for a predetermined time, connection switching for energizing and driving the electromagnetic coil of the fluid control valve in two directions. Means for driving the electromagnetic coil with an applied current smaller than the first predetermined current.

According to a second aspect of the present invention, there is provided a fluid control valve driving device, wherein an electromagnetic coil constituting the fluid control valve is driven at a first predetermined current for a predetermined time to hold a position at a first location. A second coil having a second current smaller than the first predetermined current;
In a fluid control valve driving device that is driven by a predetermined current for a predetermined time and held at a second position, a first predetermined current is generated by applying a supply voltage, and a second predetermined current is generated by applying the supply voltage to PWM.
It is characterized by being driven and generated.

According to a third aspect of the present invention, there is provided a fluid control valve driving device according to the second aspect, wherein the second predetermined current is 70% of the value of the first predetermined current. .

According to a fourth aspect of the present invention, there is provided a fluid control valve driving device, wherein an electromagnetic coil constituting the fluid control valve is driven at a first predetermined current for a predetermined time to hold a position at a first location, or A second coil having a second current smaller than the first predetermined current;
In a fluid control valve driving device that is driven by a predetermined current for a predetermined time to maintain a position at a second location, a first predetermined current is generated by PWM driving a supply voltage, and the first predetermined current is gradually increased. The first predetermined current is generated by applying a supply voltage to the electromagnetic coil.

According to a fifth aspect of the present invention, there is provided a fluid control valve driving device having the configuration of the first, second, or fourth aspect, wherein an electromagnetic coil constituting the fluid control valve is driven by a first predetermined current for a predetermined time. In a fluid control valve driving device, the position is held at a first position by a predetermined time, or the electromagnetic coil is driven at a second predetermined current smaller than the first predetermined current for a predetermined time to hold the position at the second position. It is characterized by comprising a connection switching means constituted by an H-switch using an FET, and a control unit for controlling the connection switching means.

According to the fluid control valve driving device of the first aspect, the connection switching means for energizing and driving the electromagnetic coil in both directions includes a first predetermined current, that is, a rated voltage (rated current) for forward (opening) driving. ), And a second predetermined current smaller than the first predetermined current is applied in the reverse direction (closing operation) drive, so that the resistor R is not required.

According to the fluid control valve driving device of the second aspect, in the case of the reverse direction (closing operation) driving, PWM driving is performed,
In the forward direction (for the opening operation, for example, current is applied at an energizing ratio of 80%. In this case, the average value of the applied current is
%, And the average value of the applied power is 64% of the rated power. Further, the supply voltage itself may be varied and used as the applied current.

According to the fluid control valve driving device of the third aspect, in the case of driving in the reverse direction (closing operation) using the driving circuit,
PWM drive is performed, and the energization ratio is 70% in the forward direction (open drive). The average value of the applied current is 70% of the rated current, and the average value of the applied power is 49% of the rated power.

According to a fourth aspect of the present invention, in the case of forward (opening) drive using a drive circuit,
The PWM drive is performed, the energization ratio is gradually changed from the start of energization, and the rated current is applied at the final end. The average value of the applied current gradually increases.

According to the fluid control valve driving device of the fifth aspect, a control signal is output from the control unit according to a predetermined procedure (program), and the H-switch (connection switching means) of the MOS-FET is used to control the solenoid valve. The coil is driven in a forward direction (opening operation) or in a reverse direction (closing operation).

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a fluid control valve driving device according to the present invention will be described below with reference to the drawings. Note that an example of the electromagnetic valve targeted by this embodiment is the electromagnetic valve in FIG. FIG. 1 is a block diagram of a drive device for a fluid control valve according to the present invention. As for supply power 10, DC power generated by an AC / DC converter or the like is switched by a positive line BL + and a negative line BL-. 406. The connection switching unit 406 is controlled by a control signal from the control unit C1, switches the polarity of the DC power, and supplies the DC power to the electromagnetic coil 101 of the solenoid valve. The electromagnetic coil 101 is opened in the forward conduction mode indicated by the solid arrow, and closed in the reverse conduction mode indicated by the broken arrow.

FIG. 2 is a sequence diagram of the PWM driving in the first embodiment. In the case of the opening operation, a supply voltage is applied for, for example, 3 seconds as shown in FIG. 2A, and in the case of the closing operation, FIG. )
As described above, for example, by repeating the PWM drive of 4 ms for energization and 1 ms for non-energization in the reverse direction for 3 seconds, an average current of 80% of the rated current is applied.

FIG. 3 is a sequence diagram of the PWM drive in the second embodiment. The forward energization is the same as that in FIG. 2A, but in the case of the closing operation, the energization is 3.5 ms in the reverse direction, and the non-energization is performed. By repeating the PWM drive of 1.5 ms for 3 seconds, an average current of 70% of the rated current is applied.

FIG. 4 is a diagram showing a first example of the connection switching means 406 in FIG. This circuit is a typical example of a bipolar IC, in which a bias current of about 10 mA flows. The signal S1 is a forward / reverse switching signal, and the signal S2 is a conduction / severe conduction signal (ON / OFF). The DC power supplied via the positive line BL + and the negative line BL− is converted into the first to fourth transistors TR1 and T1 by the signals S1 and S2 via the signal converter 70.
By switching between conduction and non-conduction of R2, TR3, and TR4, the current flows through the electromagnetic coil 101 in one of a forward direction (solid arrow) and a reverse direction (dashed arrow).

FIG. 5 is a circuit diagram of the third embodiment and a sequence diagram for converting a drive voltage (current) of the electromagnetic coil. The variable voltage DC / DC converter 40 'and the connection switching means 406 shown in FIG. 5A are controlled by the control unit C1.
The control unit C1 is configured to flow a DC current supplied to the electromagnetic coil 101 in a forward direction (solid line arrow) and in a reverse direction (dashed arrow). In the forward direction (opening operation), the supply voltage is supplied, for example, for 3 seconds as shown in FIG. 5B, and in the reverse direction (closing operation), the supply voltage is 70.7% as shown in FIG. 5B. Energize at% for 3 seconds. As a result, the current ratio can be defined as 1: 0.71 and the power ratio can be defined as 1: 0.49, and the solenoid valve (structure side) may determine the constituent requirements with this as a target.

In particular, the effect can be obtained in a fuel cell power generation system and an automobile device (electric vehicle). That is, in an automotive electrical device whose power supply voltage changes from 9 to 16 V DC, the voltage is DC / DC converted (up-converted) to generate 24 V DC for an open operation and 17 V DC for a closed operation. The effect is obtained that the fluid control valve can be driven stably with respect to fluctuations in the power supply voltage.

FIG. 6 is a diagram showing a drive circuit using a MOS-FET according to the fourth embodiment, which is an example of a drive circuit in which a bias current of about 0.1 mA flows. The signal S3 is a forward (opening) control signal, and the signal S4 is a reverse (closing) control signal (PWM control). The two signals S3 and S4 from the control unit C1 are different from those in FIG. Further, in this example, a simultaneous output prohibition unit for prohibiting simultaneous output of the signals S3 and S4 to the connection switching unit 406 is provided to prevent a short circuit between the positive line BL + and the negative line BL-.

FIG. 7 is a diagram showing a conventional example for the fourth embodiment. FIG. 7A shows a driving circuit using a conventional transistor. A buffer is used to supply a base current (for example, 5 to 10 mA) to a subsequent transistor to drive the transistor.
Although the remaining voltage when one transistor is ON is as low as about 0.3 V, it requires a large amount of base current (double with one valve), and when a large number of fluid control valves are used, a considerable current is required. is there.

FIG. 7B shows a drive circuit using Darlington transistors. A buffer is not required because of the Darlington configuration, but the remaining voltage when one transistor is ON is as large as about 1.2V. Therefore, although the base current (for example, 0.3 mA) is small, the remaining voltage at the time of ON becomes approximately 2.4 V. For example, when the supply voltage is DC 12 V, the driving voltage of the electromagnetic coil becomes 9.6 V, which is widely used. For an electromagnetic coil with a rated voltage of 12 V DC, the voltage at the time of “opening operation” becomes 80% of the rated voltage, and “opening operation” depends on the differential pressure ΔP between valve ports of the solenoid valve.
I'm worried about the stability of. Also, the transistor itself is ON
This is not preferable because extra power is consumed depending on the remaining voltage at the time.

FIG. 8 is a drive sequence diagram of the fifth embodiment, showing PWM drive for gradually increasing the average current when the valve is opened. In the above-described embodiment, for example, 3
Although the rated current is applied for a second, the fifth embodiment is an example in which PWM driving is performed to reduce impact. For example,
An example is shown in which the energization ratio is increased by 10% every 0.25 seconds. Finally, the rated current is supplied for 0.75 seconds to ensure the "open operation". FIG. 9 is a characteristic diagram of the differential pressure ΔP between the valve ports and the applied current necessary for the “opening operation” at the time of the differential pressure. The applied current for “opening operation” is set even at the differential pressure ΔP1 larger than the maximum operating pressure difference ΔP required for the fluid control valve, and the rated current is determined.

FIG. 10 is a circuit diagram showing a sixth embodiment.
For example, it is a drive circuit of a fluid control valve having two electromagnetic coils 111 and 112. It goes without saying that the electromagnetic coil 111 and the electromagnetic coil 112 are wound in opposite directions. The connection switching means 406 'is typically composed of two NPN type bipolar transistors. (Of course, a configuration using a MOS-FET is desirable.) Control unit C
1 outputs a control signal to the connection switching means 406 'to control the energization of the electromagnetic coil 111 and the electromagnetic coil 112, the electromagnetic coil 111 is driven at a rated current, and the electromagnetic coil 112 is
WM drive is performed.

FIG. 11 is a circuit diagram and a drive sequence diagram of the seventh embodiment. The circuit shown in FIG. 11A converts AC power into AC / AC by four triacs t1, t2, t3, and t4.
The power distribution is performed simultaneously with the DC conversion. Triac t
The gates at 1, t2, t3 and t4 are respectively triggered by the circuit of FIG. Optical elements p1, p2, p3, p
4 is disposed adjacent to the triacs t1, t2, t3, and t4, respectively.
At 3 and t4, the gates are triggered by the emission of the corresponding optical elements p1, p2, p3 and p4. And the electromagnetic coil 1
When energizing to 01, in the case of forward energizing, FIG.
As shown in (b), a trigger is started at the zero-cross point and full-wave rectification is performed to generate a rated voltage. In the case of reverse energization, after a predetermined time (phase angle) has elapsed from the zero cross point as shown in FIG. 11C, a trigger is started and rectified to generate a predetermined voltage smaller than the rated voltage. . (Thus, the applied currents are different.) The seventh embodiment and an eighth embodiment described later are suitable for use in an air conditioner or the like to which AC power is supplied.

FIG. 12 is a circuit diagram and a drive sequence diagram of the eighth embodiment. The circuit of FIG. 12A has an AC power supply, a triac t5 (rectifier) and an electromagnetic coil 101 connected in series, and a capacitor c1 connected in parallel with the electromagnetic coil 101. The trigger of the triac t5 is given by the optical element p5. Then, when energizing the electromagnetic coil 101, in the case of forward energizing, FIG.
Starting at the zero-crossing point as shown by b in FIG. 2 (B), the current is rectified, smoothed by the capacitor c1, and a rated voltage is generated. In the case of reverse energization, after a predetermined time (phase angle) elapses from the zero-cross point as shown by c in FIG. 12 (B), the trigger is started, rectified, and smoothed by the capacitor c1 so that the voltage becomes higher than the rated voltage. Generate a small predetermined voltage. (Thus, the applied current is different.)

[0033]

As described above, according to the fluid control valve driving device of the first aspect, the connection switching means for driving the electromagnetic coil in both directions is a first predetermined current, that is, a forward (opening) drive. Is applied with a rated voltage (rated current), and a second predetermined current smaller than the first predetermined current is applied in the reverse direction (closing operation) drive. , Energy saving can be realized.

According to the fluid control valve driving device of the second aspect, the same effect as that of the first aspect can be obtained, and the degree of the applied current at the time of "opening the valve" and at the time of "closing the valve" can be arbitrarily selected. Since it is possible, tuning (matching: matching) between the control unit and the solenoid valve can be freely performed. This is suitable for use in home electric appliances that mass-produce one type of solenoid valve.

According to the fluid control valve driving device of the third aspect, the same effects as those of the second aspect can be obtained, and the driving circuit can be used to perform the forward direction (opening operation) and the reverse direction (closing operation). Is regulated to 1: 0.7 and the power ratio to 1: 0.49, so that the structural side may determine the constituent requirements with this as a target. This is suitable for use in industrial equipment that produces many types of solenoid valves in small quantities. In particular, in a fuel cell power generation system, it is desired to reduce the electric power as much as possible, and a suitable driving device can be provided.

According to the fourth aspect of the present invention, in the case of forward (opening) drive using a drive circuit,
Since the PWM drive is performed and the energization ratio is gradually changed from the start of energization, and the rated current is applied at the final end, the sound at the time of opening the valve is reduced, and the impact is reduced and the life of the structural member is extended. Become.

According to the fluid control valve driving device of the fifth aspect, a control consonant is output from the control unit according to a predetermined procedure (program), and the coil of the solenoid valve is sequentially turned on by the H-switch using the MOS-FET. Since driving in the direction (opening operation) or driving in the opposite direction (closing operation) is performed, a configuration using an IC can be used, and the configuration is simple and space saving can be realized.

[Brief description of the drawings]

FIG. 1 is a block diagram of a drive device for a fluid control valve according to an embodiment of the present invention.

FIG. 2 is a sequence diagram of PWM driving according to the first embodiment of the present invention.

FIG. 3 is a sequence diagram of PWM driving according to a second embodiment of the present invention.

FIG. 4 is a diagram showing a first example of connection switching means according to the embodiment of the present invention.

FIG. 5 is a circuit diagram of a third embodiment of the present invention and a sequence diagram in a case where a drive voltage of an electromagnetic coil is converted.

FIG. 6 is a diagram illustrating a drive circuit using a MOS-FET according to a fourth embodiment of the present invention.

FIG. 7 is a diagram showing a conventional example for a fourth embodiment of the present invention.

FIG. 8 is a drive sequence diagram according to a fifth embodiment of the present invention.

FIG. 9 is a characteristic diagram of a differential pressure between valve ports and an applied current necessary for an “opening operation” at the time of the differential pressure according to a fifth embodiment of the present invention.

FIG. 10 is a circuit diagram showing a sixth embodiment of the present invention.

FIG. 11 is a circuit diagram and a drive sequence diagram of a seventh embodiment of the present invention.

FIG. 12 is a circuit diagram and a drive sequence diagram of an eighth embodiment of the present invention.

FIG. 13 is a sectional view showing a closed state of a latch-type solenoid valve according to the present invention.

FIG. 14 is a view showing operating characteristics when the solenoid valve is detached.

FIG. 15 is a diagram illustrating a first example of a conventional driving circuit.

FIG. 16 is a diagram illustrating a second example of a conventional driving circuit.

[Explanation of symbols]

 Reference Signs List 10 supply power 406 connection switching means C1 control unit 101 electromagnetic coil TR1, TR2, TR3, TR4 transistor t1, t2, t3, t4 triac P1, P2, P3, P4 optical element

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Koji Fujisaki 535 Sasai, Sayama-shi, Saitama Prefecture Sagimiya Manufacturing Co., Ltd., Sayama Plant (72) Inventor Seiichi Nakahara 535 Sasai, Sayama-shi, Saitama F-term (reference) 3H106 DA13 DA23 DB02 DB12 DB23 DC04 DD03 EE20 EE22 FA04 FA07 FB33

Claims (5)

[Claims] An electromagnetic coil forming a flow path switching valve is driven at a first predetermined current for a predetermined time to hold a position at a first position, or the electromagnetic coil is driven at a second predetermined current for a predetermined time. And a connection switching means for energizing and driving an electromagnetic coil of the fluid control valve in both directions, wherein the second predetermined current is controlled by an applied current smaller than the first predetermined current. And a step of driving an electromagnetic coil. 2. An electromagnetic coil constituting a fluid control valve is driven at a first predetermined current for a predetermined time to hold a position at a first position, or the electromagnetic coil is moved to a second predetermined current smaller than the first predetermined current. In the fluid control valve driving device that is driven by an electric current for a predetermined time and held at a second position, a first predetermined current is generated by applying a supply voltage, and a second predetermined current is generated by PWM driving the supply voltage. A fluid control valve driving device, characterized in that: 3. The method according to claim 2, wherein the second predetermined current is 70% of a value of the first predetermined current. 4. An electromagnetic coil constituting the fluid control valve is driven at a first predetermined current for a predetermined time to hold a position at a first position, or the electromagnetic coil is moved to a second predetermined current smaller than the first predetermined current. In the fluid control valve driving device that is driven by the electric current for a predetermined time to maintain the position at the second location, the first predetermined current is generated by PWM driving the supply voltage, and the first predetermined current is gradually increased. A drive device for a fluid control valve, wherein a first predetermined current is generated by applying a supply voltage to an electromagnetic coil. 5. An electromagnetic coil constituting a fluid control valve is driven at a first predetermined current for a predetermined time to hold a position at a first location, or the electromagnetic coil is driven at a second predetermined current smaller than the first predetermined current. A fluid control valve driving device that is driven by an electric current for a predetermined time to maintain a position at a second position, comprising: a connection switching unit configured by an H-switch using a MOS-FET; and a control unit that controls the connection switching unit. The drive device for a fluid control valve according to claim 1, 2, or 4, further comprising: