JPS6029032B2 - Damper control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a damper control device, and more particularly to a damper control device including means for selectively controlling the cross-sectional area at the entrance of an orifice.

More particularly, the present invention relates to a damper control system that provides selective damping during fluid flow start or stop transitions. In many cases, it is desirable to dampen transients in and out of a given state of a flow system.

When filtering a gas stream using, for example, a fabric filter bag, it is desirable to avoid sudden waves in the gas stream when the gas control damper device is activated. Rapid waves in the gas flow cause the fabric filter bag to collapse and expand rapidly, thereby reducing the strength of the fabric of the filter bag. The decrease in strength of the fabric is particularly significant when glass fiber is mixed in. Conventional damper systems, such as "bullseye" dampers and "butterfly" dampers, operate satisfactorily only when using expensive timed actuators for relatively slow operation.

Even then, "butterfly" dampers are particularly difficult to use. This is because most of the fluid can be controlled when the damper blade moves to a position parallel to the direction of flow, so the change in flow rate is not linear with respect to change in the position of the damper blade. The "Bullseye" damper has a linear flow rate change over the entire stroke of the damper blade.
Better than "Butterfly" damper. No. 3,898,9 for providing a damper with a control device that selectively controls the opening and closing of an orifice to provide selective damping during transients that start or stop flow through the orifice.
No. 97 proposes using an electrical damper actuator to move the damper blade from one position to another.

This prior patent requires energizing one solenoid when the damper is in the open position. Also, if the device of this prior patent is combined with a furnace system using a filter back housing and the damper assembly is placed in the inlet air system of the filter back housing, the damper will be closed during cleaning and one solenoid will be removed. energizes, but another solenoid must be energized. When the overflow system is brought back into flow and quiet expansion is required, the first solenoid described above shall be energized and the second solenoid shall be deenergized until a predetermined distance or time is satisfied. No. When changing from a low flow rate to a high flow rate, the deenergized solenoid is reenergized to open the damper and maintain it in the energized position during normal operation. The present invention recognizes the desirability of providing a damper control system for selectively controlling the opening and closing of an orifice, and further ``provides a damper control system that is simple, inexpensive, easy to assemble and maintain. This was done in recognition of the desirability of

An object of the present invention is to provide a damper control device in which the damper assembly is placed at an intermediate position between the orifice fully closed position and the orifice fully open position for a predetermined period of time before moving the damper assembly from the orifice fully closed position to the orifice fully open position. is to provide.

The present invention provides a damper control device for controlling movement of a damper assembly relative to an orifice, the damper control device being assembled to the damper assembly to move the upper damper assembly relative to the orifice. The combined damper assembly moving device and the damper assembly are moved into one
an actuator for actuating the damper assembly moving device for movement from one position to another, the actuator being actuated in response to first and second control circuits to move the damper assembly from one position to another; The first control circuit includes first and second solenoids that control the three-dimensional displacement device;
The branch circuit has a three-way control switch with a first contact closed, a normally closed contact switch, a normally open contact relay switch, and the first solenoid in series, and a timer in parallel with the normally closed contact switch. 'b' The second branch circuit has a three-way control switch that closes the first point, a normally open limit switch, and a contact relay in series, and the three-way control switch closes the first contact. When the normally open IJ mitt switch is closed, the contact relay is energized to close the normally open contact relay switch, and the normally closed contact switch remains in its normally closed position, causing the first solenoid to close. and energizing a timer element of the timer; [ii] the second control circuit includes a first solenoid activation circuit for energizing the first solenoid; and a first solenoid actuating circuit for energizing the second solenoid. {a} The first solenoid operating circuit has the first solenoid and the three-way control switch with the second contact closed in series; b} The second solenoid operating circuit includes the second solenoid and the third solenoid.
in series with the above three-way control switch with the contact closed,
The three-way control switch is characterized in that it closes the third contact and at the same time closes the second contact.

The present invention advantageously provides a simple damper control device having means for controlling the opening and closing of the orifice.

The present invention further provides a damper control system that is inexpensive, robust, easy to operate, quick, and effective. The present invention also uses a solenoid valve for quiet inflation of the bag, such as when a gas filter bag is introduced into the stream, and maintains the damper in a fully closed position when the solenoid valve is energized, so that both solenoids are closed. To provide a damper control device useful for maintaining a fully open position or a normal operating state when deenergized, and for energizing one solenoid and holding the other solenoid in an intermediate holding position when deenergized. Embodiments of the present invention will be described in detail below with reference to the drawings.

The damper assembly 2 of the device shown in the figure is a damper assembly moving device such as a fluid (generally hydraulic or gas pressure) cylinder 4.
It operates in response to the operation of.

However, the damper blade moving means may also be other mechanical devices such as a motor drive in combination with suitable gearing. Fluid pressure for actuating the illustrated fluid cylinder 4 is supplied from an actuating device. This actuating device is, for example, a spring-returning, three-position, electrically piloted, remote-controlled, single-coil solenoid valve 6 which is connected via line 8 to chamber A of cylinder 4 and via appropriate line 10 to cylinder 4. The fluid is supplied to the other chamber B of 4. Chambers A and B of the cylinder 4 are defined by the position of a piston 82 (described later). The supply of fluid to cylinder 4 is determined by the position of sliding portion 20 of valve 6 in response to actuation of coil solenoids 12,14.

The solenoids 12, 14 each include biasing means 16, 18 which, when energized, cause the sliding portion 20 in the housing 24 to
The position of determines the line that supplies fluid to the selected chamber of the cylinder 4. If the damper assembly moving device 4 is, for example, a motor drive with a gear arrangement, the actuating device 6 may be, for example, a reversible starter.
・The valve 6 has five flow openings □26 in the housing 24,
It has 28, 30, 32, and 34.

Closed ports 26 and 28 communicate with lines 8 and 10, respectively, openings 30 and 34 communicate with discharge lines 36 and 38, respectively, and entrance 32 communicates with fluid supply line 40 and cylinder 4 through line 4 and valve 6. supply pressure fluid to. In the figure, the solenoid 14 has biasing means 18 and further. 3
A sliding valve 15 having three flow opening rows 7, 19, 21 is provided.

Opening 17 communicates with a fluid supply line 29 which supplies pressurized fluid to cylinder 27 through valve 15 and line 25. When the solenoid 14 is energized, the door closes 2.
1 is aligned with line 25 to discharge pressure fluid cylinder 27 . When the solenoid 14 is deenergized, the opening 19 aligns with the line 25 and supplies pressure fluid from the source line 29 to the cylinder 27 through the opening 17. When solenoids 12 and 14 are deenergized, flow path 48 is in communication with pressure fluid supply lines 40 and 10, and flow path 46 is in communication with closed port 26.
and 34 to discharge fluid from the cylinder 4 through lines 8 and 38.

Energizing the solenoids 12, 14 forces the valve portion 20 of the solenoid valve 6 into a position where the flow path 44 is aligned with the openings 32 and 26, supplying fluid from line 40 through line 8 to the cylinder 4 and at the same time Road 42 opens □28,3
0 to allow line 10 and discharge line 36 to pass through each other. When the solenoid 12 is deenergized and the solenoid 14 is energized, the sliding portion 20 is locked in the home position shown and all the ports of the solenoid valve 6 are closed. solenoid 12,
The means for energizing 14 are electrical circuits, hereinafter referred to as first and second control circuits.

Each circuit has a three-way control switch 50, a first control circuit is energized by closing contacts 53 with control switch 50, and a second control circuit is energized by closing contacts 52 and 54 with control switch 50. energize. The first control circuit consists of two subcircuits, the first subcircuit having a first actuating means, for example a solenoid coil winding 78, which is the actuating winding of the solenoid 14.

The first subcircuit further includes a normally open contact relay switch 56 which is operable in response to energization of contact relay 62. A contact relay 62 including a winding 66 is energized through a two-branch circuit 64 . The second branch circuit 64 has a normally closed contact switch 68 and a normally open contact switch 53. Therefore, when the contact 53 is closed by the control switch 50 and the contact relay 62 is energized, the coil 78 is maintained in the energized state. When contact relay 62 is deenergized, normally open contact relay switch 56 opens, thereby interrupting the circuit providing electrical energy to coil winding 78. Furthermore, limit switch 68 must also be closed to maintain contact relay 62 in an energized state. The first electrical circuit is also provided with a normally closed contact switch 72 which is actuated in response to energization of a timed element 73 of a secondary limiter 74, with timed element 73 and switch 72 being in parallel with contact relay coil 66.

In operation, when the normally open IJ mitt coil 68 closes, electrical energy is supplied to the coil 66, thereby activating the contact relay 62, closing the normally open contact relay switch 56, energizing the coil 78, and timing element 73. energize. After a predetermined period of time has elapsed, timer element 73 acts to open normally closed contact switch 72. contact switch 72
When opened, the solenoid 14 is deenergized via the coil 78. The second electrical control circuit has a control switch 50 for closing the contacts 52, 54 and an electrical coil 78, 60 providing electrical energy for actuating the solenoids 14, 12, respectively. Therefore, the control switch 50
When in a position that closes contacts 52, 54, solenoids 12, 14 act to supply fluid to cylinder 4, as described above. In the first electrical control circuit, a normally open limit switch 68 is activated in response to movement of a laterally projecting arm 80 secured to a connecting rod 84.

The connecting rod 84 is fixed at one end to the damper assembly 2 and at the other end to the piston 82, and is located between the two, and is slidable through the housing 4 through the fluid-tight window. Movement of arm 80 in a direction that pushes limit switch activation arm 81 activates limit switch 68 to close and thereby energize the first electrical control circuit as previously described. The damper blade 92 is shown in a fluid-tight closed position with a seal 93 surrounding the orifice 86 and plate 87.

The blade 92 is supported and held in position by a support frame 85 and a vertical connecting rod 84 connecting the blade 92 to the piston 82 in the cylinder 4. cylinder 4
is generally a pneumatic or hydraulic cylinder operated by a control valve 6 and supported by a support frame 85 outside the flow path. A cylindrical protrusion 90 is attached to the orifice side of the damper blade 92, and the cross-sectional area of the flow path is made constant at a predetermined portion of the stroke of the damper blade 92. At a predetermined portion of the stroke of the damper blade, a cylindrical protrusion 90'
through the orifice 86 and thereby the orifice 8
6 and the side wall of the protrusion 90 defines an annular opening ○. During the initial stage of opening of the damper assembly 2, the damper blade 92 is raised upwardly from a fluid-tight position on the seal 93. At this time, since the cylindrical projection 90 is located in line with the orifice 86, a constant flow of fluid flows through the annular gap between the cylindrical projection 90 of the damper assembly 2 and the plate forming the orifice 86. Pass. The cylindrical protrusion 90 acts as a shock absorber and has the effect of smoothing out transient changes when, for example, a cloth filter bag is returned to the flow after cleaning. In normal cases, for example, when a bag housing containing a large number of cloth filter bags is used, the initial relationship of the orifice 86 is such that the arm 80 contacts the contact arm 81 and stops the movement of the damper assembly 2. Only 1 to 2 inches (25.4 to 50.8 willows) before cutting. For precise control of the damper blade leaving the orifice 86, the cylindrical protrusion 9 is not necessary. The damper assembly may have other configurations as described in U.S. Pat. No. 3,752,43.

However, as mentioned above, when utilizing the damper assembly 2, the cross-sectional area of the orifice is variable during its ascent. Next, the variable area orifice is stopped at a position a predetermined distance from the closed opening 86 of the wall 87, ie, at a slightly open position. After the damper assembly 2 remains in this position, the damper assembly 2 moves to the fully open position when the actuator is enabled.

[Brief explanation of the drawing]

The figure is an elevational view, partially in section, of one embodiment of the invention, with electrical and hydraulic circuits shown schematically. 2... Damper assembly, 4... Damper assembly moving device (cylinder), 6... Actuation device (solenoid valve), 12, 14... Solenoid, 50...
... 3-way control switch, 52, 53, 54... Contact, 56... Normally open contact relay switch, 62.
...Contact relay, 68...Normally open lj mitt switch, 72...Normally closed contact switch, 74
・・・・・・Timer.

Claims (1)

[Claims] 1 A damper control device for controlling movement of a damper assembly 2 relative to an orifice 86, the damper control device comprising a damper control device for controlling movement of a damper assembly 2 relative to an orifice 86, the damper control device comprising It consists of an assembly moving device 4 and an actuating device 6 for actuating the damper assembly moving device for moving the damper assembly from one position to another, the actuating device comprising a first and a second a first control circuit operated in response to a control circuit to control the damper assembly moving device;
and second solenoids 12 and 14, (i) the first control circuit comprises first and second branch circuits,
(a) The first branch circuit has a third branch circuit with the first contact 53 closed.
The control switch 50, the normally closed contact switch 72, the normally open contact relay switch 56, and the first solenoid 14 are arranged in series, and the timer 74 is arranged in parallel with the normally closed contact switch 72; The branch circuit includes a three-way control switch 50 that closes the first contact 53, a normally open limit switch 68, and a contact relay 62 in series, and the three-way control switch 50 closes the first contact 53 and
When the normally open limit switch 68 is closed, the contact relay 62 is energized to close the normally open contact relay switch 56, the normally closed contact switch 72 remains in its normally closed position, and the first solenoid 14 and energizing the timer element 73 of the timer 74;
(ii) The second control circuit includes the first solenoid 14
a first solenoid operating circuit for energizing the second solenoid 12; and a second solenoid operating circuit for energizing the second solenoid 12; 14 and the three-way control switch 50 with the second contact 54 closed in series, (b)
The second solenoid operating circuit has the second solenoid 12 and the three-way control switch 50 that closes the third contact 52 in series, and the three-way control switch closes the third contact 52. A damper control device characterized in that the second contact 54 is closed at the same time.