JPH09217249A - Brake device of loom - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a loom-braking device capable of continuously giving a braking force to the main shaft of a loom in a little consumption energy also after power failure. SOLUTION: This device for allowing braking forces to act on the main shaft of a loom contains the first braking means which is operated, when electricity is charged, and the second braking means which is operated, when electricity is not charged. The second braking means 12 contains a braking mechanism 34 for converting the pressure of a hydraulic fluid into a braking force, and a control valve 32 disposed in a passage for connecting the braking mechanism 34 to a hydraulic fluid source 30 and for allowing the braking mechanism to communicate with the hydraulic fluid source 30, when the electricity is not charged.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a braking device for directly or indirectly applying a braking force to a main shaft of a loom,
Particularly, the present invention relates to a braking device that positively applies a braking force to a main shaft even when the braking device is not energized, that is, even when a power failure occurs.

The term "blackout" in the present specification refers to an inevitable so-called normal power failure as well as a weaving machine caused by an accident, a human error, or an intentional thing in the weaving factory as required. It also includes stopping the power supply to.

[0003]

2. Description of the Related Art A so-called braking device (hereinafter referred to as a "main body brake") for applying a braking force to a main shaft of a loom has a so-called braking force applied to the main shaft when energized. There is an electromagnetic brake that operates when energized.

The energized electromagnetic brake energizes the exciting coil of the electromagnetic brake to generate a braking force in the energized state of the exciting coil. However, in a loom equipped with such a braking device, when a power failure occurs while the loom is in operation or stopped, the main body brake does not operate, which causes various problems.

For example, when the loom is in operation, the braking force does not act on the main shaft, so that the main shaft continues to rotate by inertia (inertial force) and stops when the inertial force disappears. As a result, the state of the spindle when stopped, such as the rotation angle of the spindle when stopped, is not constant, and the mouth-matching operation at the time of restart is troublesome.
Further, the weaving pattern may be displaced, which may cause a defect in the woven fabric.

When the loom is stopped due to a weft stop or the like,
Since the main body brake is energized, the main shaft is maintained in the stopped state by the braking force of the main body brake, and the opening device driven by the main shaft and the heddle frame connected to the opening device are also stopped at the same time. The state is maintained. When a power failure occurs in such a state, the braking force acting on the main shaft suddenly disappears, and at the same time, the force for maintaining the opening device and the heddle frame also disappears. As a result, when the opening device is a depolarizing opening device, the following phenomenon occurs.

Depending on the stopped state of the loom, the spring force for the depolarizing shedding device may cause the main shaft to stop in a state in which a force for rotating the main shaft acts. If the braking force on the main shaft disappears in such a state, the heddle frame may suddenly move and damage the warp, the woven fabric, or the like. In addition, the phenomenon as described above is dangerous for an operator who is performing repair work for the cause of stoppage.

Further, there is a conventional electromagnetic brake that operates when energized, in which a capacitor is arranged as an auxiliary power source in the power circuit of the electromagnetic brake. In this braking device, the capacitor is charged during operation, and when a power failure occurs, the electric power stored in the capacitor is supplied to the exciting coil to apply a braking force to the main shaft. However, the time that the exciting coil can be kept in the excited state by the electric power stored in the capacitor is very short, so it is possible to stop the rotation of the main shaft, but continue to apply the braking force to the main shaft to stop it. It is impossible to maintain the condition. As a result, the same problems as in the energized electromagnetic brake without such a capacitor occur.

As a conventional technique for solving the above problem, there is an apparatus described in Japanese Patent Application Laid-Open No. 7-316956. In this device, an electromagnetic brake that operates when energized and an electromagnetic brake that operates when not energized are installed side by side, and both are selectively used according to the operating state of the loom. The non-energized electromagnetic brake generates braking force when it is not energized, so by using this as a holding device after stopping, the initial state of stopping is maintained even if a power failure occurs. can do. Further, in this device, the electromagnetic brake of non-energizing type is used only as a holding device, so that the power consumption is reduced as compared with the conventional electromagnetic brake of non-energizing type.

However, even with such a braking device, power consumption cannot be avoided. That is, when the machine is stopped, the main shaft of the loom is subjected to the spring force of the depolarizing opening device, the gravity of the heddle frame, and the like, and the spring force of the electromagnetic brake for maintaining this is also large. Therefore, the excitation power that continues to be supplied to the excitation coil during operation also inevitably increases, and power consumption is unavoidable. Further, since the non-energized electromagnetic brake in this conventional device does not have a braking force enough to brake the main shaft of the loom during operation, if a power failure occurs during operation, the stop position of the main shaft will be constant. However, the same problem as the electromagnetic brake that operates when energized occurs.

[0011]

SUMMARY OF THE INVENTION An object of the present invention is to consume a small amount of energy and to make it possible to continuously apply a braking force to the main shaft of a loom even after a power failure occurs.

The "braking force" in the present invention includes not only the force for braking the main shaft of the loom in operation, but also the force for maintaining the stopped state of the main shaft of the loom during stop.

[0013]

A braking device for a loom according to the present invention comprises:
A device for applying a braking force to a main shaft of a loom, the device including a first braking device that operates when energized and a second braking device that operates when not energized, and the second braking device. Is provided in a braking mechanism that converts the pressure of the pressure fluid into a braking force, and a flow path that connects the braking mechanism and the pressure fluid source. When not energized, the braking mechanism communicates with the pressure fluid source. And a control valve for controlling

The first braking means is driven so that the braking force acts on the main shaft when the power is not supplied. The control valve keeps the pressure fluid source and the braking mechanism of the second braking means in a non-communication state when there is no power outage, and keeps the pressure fluid source and the braking mechanism of the second braking means in a communication state when there is a power failure. To be controlled. Therefore, when a power failure occurs, the braking mechanism of the second braking means is connected to the pressure fluid source via the control valve, so that the braking mechanism of the braking mechanism of the second braking means causes the pressure fluid from the pressure fluid source to flow. The braking force acts on the main shaft.

The electric power required to maintain the control valve so as to keep the braking mechanism and the pressure fluid source in a non-communicated state at the time of non-power failure generates a suction force of a magnitude that overcomes the spring force for generating the braking force. Very small compared to the power needed to. In addition, the amount of the pressure fluid discharged after the restoration from the power failure is small. Further, in the second braking means, the braking mechanism and the flow path connected thereto are kept airtight enough, so that the pressure of the pressure fluid acting on the braking mechanism is kept constant, and after the occurrence of the power failure. Can also apply a constant braking force to the spindle.

As described above, according to the present invention, the first braking means that is actuated when energized and the second braking means that is actuated when not energized are used. It includes a braking mechanism that converts pressure into braking force, and a control valve that brings the braking mechanism and the pressure fluid source into communication when power is cut off. Power can continue to be applied.

The pressure fluid is compressed air, and the second
The braking means includes a pressure converter that converts the pressure of the compressed air supplied through the control valve into the pressure of hydraulic oil, and a hydraulic brake that is driven by the hydraulic oil of the pressure converter. preferable. As a result, the pressure fluid source can be shared with the pressure fluid source used in the other mechanism of the loom.

The first braking means is an electromagnetic brake,
An energization circuit that supplies electric power to the electromagnetic brake is preferably provided, and the energization circuit preferably includes a capacitor that stores electric power when energized and supplies the stored electric power to the electromagnetic brake during a power failure. With this, the braking force can be applied to the main shaft by the first braking means for a certain time after the occurrence of the power failure, so that even if there is a response delay in the operation of the second braking means, the main shaft will not operate after the power failure occurs. It is maintained by the first braking means until the second braking means is activated.

In the preferred embodiment, the control valve comprises a first port in communication with the source of pressure fluid, a second port in communication with the braking mechanism, a third port in open, and a second port. A valve body that selectively communicates the port with either the first or third port, a spring that moves the valve body to communicate the second port with the first port, and a spring that resists the force of the spring. An exciting coil for moving the valve body by means of a valve and a manually operated button for moving the valve body so as to forcibly communicate the second port with the third port.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1 and 2, a braking device for a loom uses a first braking device shown in FIG. 1, which operates when energized, that is, a first braking means 10 as a main body brake. In addition to the provision, the second braking device shown in FIG. 2, that is, the second braking means 12 that operates when not energized, is provided as an auxiliary brake.

The first braking means 10 which is actuated when energized includes a general electromagnetic brake. As shown in FIG. 1, the electromagnetic brake energizing circuit includes a rectifying circuit 16 for rectifying the commercial AC power source 14, a relay 18 energized by the AC from the power source 14, and an ON / OFF switch on the output side of the rectifying circuit 14. An exciting coil 22 connected via the stop contact 20 and a capacitor 24 connected in parallel to the exciting coil 22.

The exciting coil 22 is a coil of the electromagnetic brake of the first braking means 10 and is energized each time the stop contact 20 is closed. The stop contact 20 is a normally open contact, and is operated by an operator operating a stop switch (not shown) or at a preset loom braking start time in synchronization with the crankshaft by a loom control circuit. , Closed. Therefore, as long as the power supply 14 is normal, the first braking means 10 operates each time the stop contact 20 is closed, and applies the braking force directly or indirectly to the main shaft of the loom.

The normally-closed contact 18b of the relay 18 is arranged in parallel with the stop contact 20 between the exciting coil 22 and the capacitor 24, and is opened while the relay 18 is energized. The relay 18 is energized when the power source 14 is normal, and is disconnected when the power source fails due to a power failure or the like.
Therefore, the first braking means 10 charges the capacitor 24 when the power supply 14 is normal, and supplies the power accumulated in the capacitor 24 to the exciting coil 22 through the normally closed contact 18b when a power failure occurs. . As a result, the main shaft of the loom is braked by the first braking means 10 when a power failure occurs.

The relay 18 is connected to the power source 14 and the rectifier circuit 1
6, instead of arranging the relay 18 in parallel with the rectifier circuit 16, the relay 18 is arranged in parallel with the capacitor 24 between the rectifier circuit 16 and the capacitor 24 to prevent the discharge current of the capacitor 24 from flowing to the relay 18. The diode to operate may be arranged in series with the relay 18.

As shown in FIG. 2, the second braking means 12
Is a control valve 32 provided in a flow path of a working fluid such as compressed air supplied from a pressure fluid source 30, that is, a pressure fluid.
And a braking mechanism 34 that converts the pressure of the pressure fluid supplied via the control valve 32 into a braking force. The control valve 32 is
It is a three-way valve and is provided in the fluid flow path that connects the braking mechanism 34 and the pressure fluid source 30.

As shown in FIG. 3, the control valve 32 includes first and second casings 36, 38 coaxially coupled to each other.
And the insert 4 arranged in the first casing 36
0, the first, second and third ports 42, 44 and 46 formed in the first casing 36, and the port 44.
And a valve body 48 for selectively communicating the port with one of the ports 42 and 46, and the port 44 with the port 4
The compression coil spring 50 for urging the valve body 48 to communicate with the second coil, the exciting coil 52 for moving the valve body 48 against the force of the spring 50, and the valve body 48 for communicating the port 44 with the port 46. A manually operated push button 54 that is manually moved and a plunger 56 that is disposed within the excitation coil 52.
And

The space inside the insert 40 is defined by the insert 4
It is divided into three spaces by a plurality of sealing members 58 arranged at 0. The ports 42, 44, 46 communicate with the space inside the insert 40. The port 42 is in communication with the pressure fluid source 30, the port 44 is in communication with the fluid inflow path of the braking mechanism 34, and the port 46 is open to the atmosphere.

The valve body 48 extends in the insert 40 and the exciting coil 52, and one end of the valve body 48 penetrates the plunger 56. The spring 50 is disposed in the insert 40, has a biasing force for moving the valve body 48 upward, and exerts a pressing force for displacing the valve body 48 upward on the valve body 48. . A cap 62 is fixed to the upper end of the plunger 56, and a compression coil spring 60 is arranged in a casing formed by the plunger 56 and the cap 62.

The spring 60 is for absorbing a shock when the valve body is moved, and its urging force is larger than that of the spring 50, but the spring 60 pushes the valve body together with the plunger 56. The pressure is such that pressure can be applied to the valve element 48. The button 54 is arranged in the casing 38 so that the valve body 48 can be moved to the spring 50 side via the pusher 62, the plunger 56 and the spring 60.

Referring again to FIG. 2, the braking mechanism 34 is
A pressure converter 70 for converting the pressure of the pressure fluid supplied through the control valve 32 into the pressure of hydraulic oil, and a hydraulic brake 72 driven by the hydraulic oil of the pressure converter are provided. The hydraulic brake 72 is a known brake including a hydraulic cylinder driven by the pressure of the hydraulic oil from the pressure converter 70, a pad that is pressed against the brake disc 74 by the hydraulic cylinder, and the like. The brake disc 74 is attached to the main shaft of the loom or an auxiliary shaft that is operatively connected to the main shaft, and is braked by pressing a pad to apply a braking force to the main shaft of the loom.

When the power source is normal, the exciting current is constantly supplied to the exciting coil 52 via the lead wire 64, so that the plunger 56 is attracted into the exciting coil 52 and the valve body 48 is pulled.
Is moved to the side of the spring 50 via the pusher 62 and the spring 60 to move the second and third ports 44, 46 to the position shown in FIG.
It connects as shown in (A). As a result, the pressure fluid source 30 is separated from the pressure converter 64 of the braking mechanism 34, and the fluid inflow path of the pressure converter 64 is communicated with the atmosphere, so that the second braking means 12 applies a braking force to the main shaft of the loom. Do not act. The second condition that the braking force is not applied to the main shaft of the loom
The force for maintaining the braking means 12 may be such a force as to move the valve body 48 against the biasing force of the spring 50 and maintain it at that position.

On the other hand, when a power failure occurs, the exciting current is not supplied to the exciting coil 52. Therefore, the valve body 48 is moved to the spring 60 side by the force of the spring 50 and the first and second ports 42, 44. To communicate with each other as shown in FIG. As a result, the pressure of the pressure fluid of the pressure fluid source 30 acts on the pressure converter 64 of the braking mechanism 34 via the control valve 32, so that the braking mechanism 34 exerts a braking force on the main shaft of the loom. At this time, since the braking mechanism 34 only generates the braking force by the pressure of the pressure fluid and consumes almost no pressure fluid, the consumption amount of the pressure fluid is extremely small.

According to the above braking device, the second braking means 12 can be maintained in a state in which the braking force is not generated with a small amount of exciting power, that is, power consumption. The energy consumption is significantly less than that of the other. Further, since the amount of pressure fluid consumed at the time of power failure is almost zero, the second braking means 12 operates stably.

As in the above embodiment, the first braking means 10
If the capacitor 24 is provided in the energizing circuit, when the power failure occurs, the first braking means 10 is driven for a short time by the electric power stored in the capacitor 24, so that the operation of the second braking means 12 is started in a timely manner. Even if there is a delay, the main shaft of the loom is surely stopped. However, if the second braking means 12 has no response delay, the capacitor 24 may not be provided.

Normally, the first braking means 10 is driven each time a loom stop command is generated as shown in FIG. 5 (B), and the second braking means 12 is driven as shown in FIG. 5 (C). It is driven every time a power failure occurs. As a result, the main shaft of the loom is rotated as shown in FIG.

However, the second braking means 12 is shown in FIG.
As shown in (D), each time a stop signal is generated, it may be further driven in synchronization with the first braking means 10. Further, as shown in FIG. 5 (E), the second braking means 12 is rotated by the first braking means 10 after a predetermined time elapses from the time when the stop command is generated, or when the rotation of the main shaft is changed. It may be driven further after being stopped by. In either case, since the first and second braking means are activated each time the stop command is generated, the first braking means is deactivated by the occurrence of a power failure while the loom is stopped. Even after switching, the main shaft is maintained in the state when the loom is stopped by the second braking means.

The pressure fluid source 30 may be commonly used as an air source for generating compressed air for weft insertion.
Alternatively, a pressure fluid supply tank dedicated to the braking means may be used.
If a pressure fluid supply tank dedicated to the second braking means is used as the pressure fluid source 30, the pressure of the pressure fluid can be set freely, so a pneumatic brake may be used instead of the hydraulic brake.

In the first braking means, instead of using the electromagnetic brake, other energizing type brakes such as a hydraulic brake and a pneumatic brake may be used. in this case,
For example, it can be a braking means similar to the second braking means 12 shown in FIG. 1, in which case the first braking means is the first of the control valves corresponding to the control valve 32 of the second braking means 12.
42 is open to atmosphere and the third port 46 is connected to a source of pressure fluid.

[Brief description of drawings]

FIG. 1 is a diagram showing an embodiment of an electric circuit of a first braking means used in the present invention.

FIG. 2 is a diagram showing an embodiment of second braking means used in the present invention.

FIG. 3 is a sectional view showing an embodiment of a control valve used in a second braking means.

FIG. 4 is a diagram for explaining the operation of the control valve shown in FIG.

FIG. 5 is a diagram for explaining a driving method of the braking device of the present invention.

[Explanation of symbols]

 10 First Braking Means 12 Second Braking Means 14 Commercial AC Power Supply 16 Rectifier Circuit 18 Relay 20 ON / OFF Stop Contact 22 Electromagnetic Brake Excitation Coil 24 Capacitor 18b Relay Normally Closed Contact 30 Pressure Fluid Source 32 Control Valve 34 Braking mechanism 42, 44, 46 port 48 Valve body 50 Spring 52 Excitation coil 54 Push button

Claims (3)

[Claims] 1. A device for applying a braking force to a main shaft of a loom, comprising: a first braking device that operates when energized; and a second braking device that operates when not energized. The second braking means is provided in a braking mechanism that converts the pressure of the pressure fluid into a braking force and a flow path that connects the braking mechanism and the pressure fluid source, and the braking mechanism and the pressure fluid when not energized. A braking device for the loom, including a control valve that places the source in communication. 2. The pressure fluid is compressed air, and the second braking means converts a pressure of the compressed air supplied through the control valve into a pressure of hydraulic oil,
The hydraulic device according to claim 1, further comprising a hydraulic brake driven by hydraulic oil of the pressure converter. 3. The first braking means includes an electromagnetic brake and an energizing circuit for supplying electric power to the electromagnetic brake, and the energizing circuit accumulates and accumulates electric power when energized. The braking device according to claim 1 or 2, further comprising a capacitor that supplies electric power to the electromagnetic brake during a power failure.