JPS6056545B2 - explosive painting equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to equipment for painting processes using hot spray technology, and more particularly to explosive painting equipment.

The invention is useful in the metallurgical industry, the oil industry, the chemical industry, the machine assembly industry, the dynamic engineering industry, and any other industry where it is desired to produce parts that are subjected to heavy loads or are exposed to strong corrosion and erosion during use. Can be used in industry. Although explosive coating technology has been known for a long time, no device has been proposed so far that ensures a good quality coating even in the event of accidental failures and at the same time ensures high operating efficiency.

Explosive coating devices generally comprising an explosion chamber made in the shape of a barrel closed at one end are disclosed in USSR Inventor's Certificate No. 438,215 and in US Pat. No. 2,714,563 and US Pat.

A spark plug that starts the explosion is installed inside this explosion chamber. The apparatus also includes a gas mixture supply system having a mixer in communication with a source of gas mixture components and the explosion chamber. A batch meter for the powder supply system is also communicated with the explosion chamber. Furthermore, the device also includes a control system including a control unit electrically connected to the spark plug, the gas mixture supply system and the powder supply system. Before operating the device, the article to be painted is placed at the open end of the explosion chamber.

A gas mixture prepared in advance in a mixer and powder coating material measured in a batch meter are supplied to the explosion chamber. An explosion is then initiated in the explosion chamber by means of a spark plug, causing the powder to interact with the surface of the part to be painted and forming a coating layer thereon. The operating sequences involved in the preparation and execution of this painting process are automatically controlled by the control system. However, during operation, if there is no powder in the batch meter, the discharge hole of the batch meter is clogged with a mass of adhering powder particles, or the vibrator connecting the batch meter to the explosion chamber is damaged. Powder may not be supplied to the explosion chamber due to clogging caused by return of powder during explosion.

However, the operation of the control system described above is not based on whether powder has been delivered to the explosion chamber or not, and therefore components of the gas mixture are wasted (idling operation of the device is not excluded). This will affect the quality of the coating formed due to the physical properties of the base material changing due to the exposure of the base material to the action of the explosion products (coating powder in the explosion chamber). (If the explosion is carried out without the
Japanese Patent No. 129169) discloses an explosive coating device that eliminates the above-mentioned drawbacks.

This device consists of an explosion chamber made in the shape of a barrel with one end closed, a spark plug installed in the explosion chamber for starting the explosion, a gas mixture supply system, a powder supply system, and a control system. It is equipped with. The gas mixture supply system includes a mixer in communication with a source of gas mixture components and an explosion chamber. The powder supply system is equipped with a batch meter that communicates with the explosion chamber. The control system of this device includes a control unit and a feedback circuit.

The control unit is electrically connected to the spark plug, the gas mixture supply system and the powder supply system. The feedback circuit includes a powder detector for detecting powder in the explosion products, which detector is located at the open end of the explosion chamber. Furthermore,
The feedback circuit also includes a signal converter for converting the signal generated by the powder detector. This signal converter is connected to the control unit. During operation, the explosion chamber contains
It is filled with a gas mixture prepared in advance using a mixer and powder coating material measured using a batch meter. An explosion is then initiated in the explosion chamber by means of a spark plug, causing the powder to interact with the surface of the article to be painted, which is placed at the open end of the explosion chamber, and to form a coating layer on this surface. The operating sequences involved in the preparation and execution of this painting process are automatically controlled by a control system. This occurs when powder is not delivered to the explosion chamber or there is a failure to ignite (i.e. the explosive mixture within the chamber does not explode), but there is no powder coating material in the direction of flow of the explosion products. for,
A signal from the powder detector is transmitted via a feedback circuit to a control unit which responds to the signal to de-energize the device and determine the reason for its failure. However, the above failures of this device occur randomly, i.e. two or three times in a row per 1000 explosions, in which case it is necessary to de-energize the device in order to determine the reason for the failure. This results in high operating costs. Furthermore, in the event of an ignition failure, powder is left behind in the explosion chamber, which is added to the next powder punch during the next explosion, so that the next explosion product stream actually contains two It will contain twice as much powder.

As a result, the heating and acceleration of the powder particles is insufficient, which prevents optimal interaction between the powder particles and the surface of the article being coated, and also prevents the powder from interfering with the surface being coated. This results in insufficient bonding with body particles, which considerably affects the quality of the finished coating. The present invention provides an explosive coating device that improves the quality of the coating and reduces downtime of the device even in the event of an accidental failure by improving the control system. It is something.
This object of the invention provides an explosion chamber made in the form of a barrel closed at one end, a spark plug for initiating an explosion mounted in this explosion chamber, and a source of components of a gas mixture and a detonation chamber located in said explosion chamber. A gas mixture supply system including a mixer communicated with each other, a powder supply system including a batch meter communicated with the explosion chamber, and a control system, the control system including the spark plug, the gas mixture supply system, and the powder supply system communicating with each other. a control unit electrically connected to the body supply system; a feedback circuit including a powder detector located at the open end of the explosion chamber to detect powder in the explosion products; and a signal converter for converting the signal generated by the powder detector, the control system further comprising: a signal converter for converting the signal generated by the powder detector; A protective blind installed at the open end of the explosion chamber behind the detector, and a control circuit including a threshold element, through which the protective blind is electrically connected to the signal converter. This is achieved by a device characterized by the following.

This improvement in the structure of the control system allows the device to continue operating even in the event of an accidental failure. In the event of a fault, the surface of the article to be coated is shielded with a protective blind until the operating characteristics of the two-phase flow are completely restored, so that the two-phase flow does not contain the explosion products and the detector. It consists of a powder coated material whose presence is detected by This greatly reduces the downtime of the device. Furthermore, initial explosions and explosions after ignition failure (i.e. explosions containing very little or very large amounts of paint powder) hit the protective blind, which is painted in such cases. It shields the surface of the article and significantly improves the quality of the applied coating.

Preferably, the control system includes a manipulator for moving the article to be painted, the manipulator being connected to a threshold element of the control circuit.

By using a manipulator, the article to be painted can be moved according to a predetermined program.

By electrically connecting the manipulator to the threshold element, the manipulator can be stopped in the event of an accidental failure of the device with the surface of the article shielded by a protective blind. When the protective blind is opened again after the operating characteristics of the two-phase flow have been restored, the parts of the article to be coated which were not coated due to the interruption in operation are coated.

All of these can increase the quality of the coating applied. Hereinafter, specific embodiments of the invention will be described in detail with reference to the accompanying drawings. Explosive coating device according to the present invention (Fig. 1)
consists of an explosion chamber 1 made in the shape of a barrel with one end closed, and a spark plug 2 installed in this explosion chamber 1 to start the explosion.
, a gas mixture supply system 3 , a powder supply system 4 , and a control system 5 .

The gas mixture supply system 3 comprises a mixer 6 which produces a gas mixture from a combustible gas such as acetylene, an oxidizing gas such as oxygen and an inert gas such as nitrogen.

The sources 7, 8 and 9 of each component of this gas mixture are connected to the valve 13.
, 14 and 15 respectively.
and 12 to the mixer 6. Mixer 6 is
It communicates with the explosion chamber 1 via a coiled vibrator 17 and a check valve 16 designed to suppress the return of gas from an explosion. The powder supply system 4 includes a batch meter 18 provided with a hopper 19, which has a first inlet 20 for loading powder coating material, a second inlet 21 for supplying gas,
It has a discharge hole 22 connected to the explosion chamber 1 via a pipe 23.

The batch meter 18 is connected to a source of carrier gas via a gas supply vibe 24 connected to a second inlet 21, which in this device is the source of inert gas 9. As the batch meter 18, a feeder with a pump connected to a source of carrier gas may be used (for example, a pulse mode feeder, a vane type flow feeder, or a gas injection feeder with a perforated ring). A valve 25 is attached to the gas supply vibe 24 at the second inlet 21 of the batch meter 18, and the carrier gas is supplied to the batch meter through this valve. The control system 5 of the device proposed here includes a control unit 26
This control unit 26 includes a control circuit 27,
28, 29 and 30 to the actuating mechanism, i.e. the valve 15 of the gas mixture supply system 3 via the circuit 28.
connected to the valves 13 and 14 via the circuit 27,
It is connected via a circuit 29 to a spark ignition device 31 (which creates a spark between the plugs 2) and via a circuit 30 to a valve 25 (through which the carrier gas is sent to the powder supply system). The control system 5 further comprises a feedback circuit 32 which is connected to a powder detector 3 mounted at the open end of the explosion chamber 1 to detect the presence of powder in the explosion products.
3 and a signal converter 34 for converting the signal generated by the powder detector 33, and the feedback circuit 32 is electrically connected to the control unit 26 via a threshold element 35.

The powder detector 33 is configured in the form of a photocell.

Since the light is emitted by the explosion products leaving the explosion chamber 1 during operation, there is no need to use an additional light source. A signal converter 34 that converts the signal from the powder detector 33 includes a voltage amplifier 36, a power amplifier 37, and an RC connected in series.
An integration network 38 and a power amplifier 39 are provided.

A voltage amplifier 36 is connected to the powder detector 33 and a power amplifier 39 is connected to the control unit 26 via a threshold element 35. Threshold element 3
5 is configured in the form of an electromagnetic relay 40, and this relay 40
are connected to control circuits 27, 29 and 30 of control unit 26 via contacts 41, 42 and 43, respectively.

At the input of this electromagnetic relay 40 is arranged a toggle switch 44 having two positions ゜a'' and ``b''.
By changing the above-mentioned position of this toggle switch 44, the electromagnetic relay 40 can be connected to the DC power source E or the powder detector 3.
3 is connected to either a power amplifier 39 of a signal converter 34 that converts the signal from 3. According to the invention, the open end of the explosion chamber 1 is fitted with a protective blind 45, which is located behind the powder detector 33 in the direction of the flow of the explosion products and which protects the explosion chamber 1. has an actuation mechanism 4 configured in the form of an electromagnet.
6 is provided.

A control circuit 47 including a threshold element 48 is connected to this actuating mechanism 46 , via which the protective blind 45 is electrically connected to the signal converter 34 of the powder detector 33 . Actuation mechanism 46 of the protective blind 45
is connected to the DC power supply E via the control circuit 47.

The threshold element 48 is made in the form of an electromagnetic relay 49, which has contacts 50 installed in the control circuit 47, and whose input is connected to the power multiplier 39 of the signal converter 34. be done.

Electromagnetic relays 40 and 49 switch contacts 41, 42, and 43 of electromagnetic relay 40 to the closed position (energized The contact holding time in the state) is the contact 5 of relay 49.
The contact holding time is selected to be longer than the contact holding time of 0.

The holding time of the contact 50 of the electromagnetic relay 49 in the closed position is 2
It is longer than the time interval between two explosions, but shorter than the time interval between three explosions.

The contact retention time in the closed position of the contacts 41, 42 and 43 of the electromagnetic relay 40 is longer than the time interval between three detonations, but shorter than the time interval between four detonations. This may occur if the failure of the device, such as the absence of powder in the flow of explosive products or the failure of the device to ignite, is repeated for a time corresponding to no more than two successive explosions. required to make this incidental. The control unit 26 is designed to repeatedly generate electrical pulses for actuating the actuation mechanism in a predetermined sequence.

This unit may be configured in various ways, for example in the form of a master controller (as shown in Figure 2). This master controller is a rotary drive device 52
The shaft 51 is connected to the shaft 51.

Cams 53, 54, 55 and 56 are mounted on this shaft 51. The cam 53 contacts a switch 57 of the control circuit 27 which actuates the valves 13 and 14, and the cam 54 contacts a switch 58 of the control circuit 28 which actuates the valve 15 of the gas mixture supply system 3. Similarly, the cam 55 contacts the switch 59 of the control circuit 29 which activates the device 31 for creating a spark between the spark plugs 2, and the cam 56 contacts the switch 59 of the control circuit 29, through which the carrier gas is supplied to the powder supply system 4. ) to the control circuit 30 which activates the switch 60. In the variant of the device according to the invention shown in FIG. connected to.

The explosive coating device proposed here operates as follows.

Before starting the operation, the article C to be painted is placed in the explosion chamber 1 (
1) and set the toggle switch 44 to position ``a''.

In response, electromagnetic relay 40 is activated, closing contacts 41, 42, and 43 of control circuits 27, 29, and 30 of control unit 26. The contacts 50 of the electromagnetic relay 49 are open and the protective blind 45 shields the surface of the article C to be painted. After performing the prestart procedure, the operator presses the bushing button '6 Star P' on the control console (neither this bushing button nor the control console are shown). In response to this, the drive device 52 of the control unit 26 (
1 and 2) is energized and a supply voltage from power source E is applied to control circuits 27, 28, 29 and 30 to operate the actuating mechanisms of the device in a predetermined sequence. In this case, first of all, the cam 53 activates the switch 57 to close the control circuit 27 and thereby activate the valves 13 and 14 of the gas mixture supply system 3, while the cam 54 activates the switch 58. to close circuit 28, thereby closing valve 15.
Activate. As a result, combustible gases, oxidizing gases and inert gases are released from their sources 7, 8 and 9 into the vibrator line 10.
, 11 and 12 to mixer 6, where these components are mixed to form an explosive mixture. The gas mixture thus created is connected to the check valve 16 and the coiled vibrator 1.
7 and is introduced into explosion chamber 1. When the explosion chamber 1 is filled with this gas mixture, the cam 56 of the control unit 26 actuates the switch 60, closing the circuit 30 and thereby actuating the valve 25 of the powder supply system 4.

The valve 25 is closed during the control circuit 30 (this is the time when the cam 5
6) and supplies inert gas (carrier gas) to the batch meter 18 which is introduced into the explosion chamber 1 through the vibrator 23. The amount of powder supplied to the explosion chamber 1 in this way (powder charge) depends on the pressure of the carrier gas and on the opening time of the valve 25. Once the explosion chamber 1 is filled with the gas mixture and the powder coating material, the cam 53 of the control unit 26 releases the switch 57 to open the control circuit 27, thereby opening the vibrator tubes for supplying the flammable gas and the oxidizing gas respectively. Valves 13 and 14 of channels 10 and 11 are closed.

At this time, the valve 15 is still open, so the inert gas continues to be supplied to the mixer 6, and the mixer 6 and check valve 1
6 and the cavity of the coiled vibrator 17 to force the gas mixture out. Cam 54 then releases switch 58 to open control circuit 28, thereby closing valve 15.

At the same time, the cam 55 actuates the switch 59, which in response closes the control circuit 29 and forms a spark between the spark plugs 2, thereby starting an explosion in the combustion chamber 1. The explosion products entrained powder coated materials;
This is heated and accelerated.

A detector 33 mounted at the outlet of the explosion chamber 1 detects the brightness of the two-phase flow, which brightness is based on the amount of powder coating material contained in the two-phase flow. The signal from the detector 33 is sent to a signal converter 34 where the power of the signal is first amplified by a power amplifier 36 and then the voltage of the signal is amplified by a voltage amplifier 3.
It is increased in width by 7. Detector 7 amplified in this way 3
The signal No. 3 is applied to an RC integration circuit 38 including a capacitor. In response to the signal from the detector 33, the capacitor of the RC integrator circuit 38 is charged to a voltage proportional to the amplitude of the signal. The voltage of the capacitor of this RC integration circuit 38 determines the voltage value of the output of the power amplifier 39. The first explosion chamber is placed against the protective blind 45.

This is, in the case of the first explosion, the content of the explosive mixture components (
This is explained by the fact that the efficiency is not sufficient since the weight (by weight) does not perfectly match the predetermined operating parameters. After the first explosion, the toggle switch is switched to position 6'b' and the device is then activated based on the signal from the detector 33. When the amount of powder contained in the explosion product corresponds to the predetermined value, the voltage output from the power amplifier 39 corresponds to the predetermined value. In this case, the electromagnetic relay 49 is actuated to close the contact 50 of the control circuit 47, and in response the actuating mechanism 46 of the protective blind 45 is connected to the DC power supply E, so that the protective blind 45 is lifted. to expose the surface of the article to be painted. If the voltage value at the output of the power amplifier 39 is sufficient to activate the electromagnetic relay 49, the device will operate in the sequence described above. The powder particles are ejected from the explosion chamber 1 by the explosion and strike the article and bond to its surface forming a coating layer. If the amount of powder coating material contained in the explosion product is less than the specified value, or if no powder is detected in the explosion product, or if the device fails to ignite (no explosion occurs) In this case, the voltage value of the output of power amplifier 39 is no longer sufficient to operate electromagnetic relays 40 and 49.

The electromagnetic relay 49 (the holding time of its contacts 50 in the closed position is shorter than the holding time of the contacts of the electromagnetic relay 40) opens the control circuit 47, in response to which the actuating mechanism 4-6 lowers the protective blind 45. The surface of the article C to be coated is thereby shielded. If the voltage value at the output of the power multiplier 39 does not reach the required value during a time equal to the corresponding time between two successive explosions, the contacts 41, 42 and . and 43 are opened and operation of the device is stopped to allow the reason for the failure to be determined.

If the voltage value at the output of the power amplifier 39 returns, this failure of the device is assumed to be accidental and the electromagnetic relay 49 is activated to close the contacts 50. As a result, it works. The mechanism 46 is activated to lift the protective blind 45 and the device then operates in a predetermined sequence. In the variant of the device of the invention shown in FIG. 3, the device operates generally as described above. However, in this case, the manipulator 61 moves the article C to be painted only when the contact 50 of the electromagnetic relay 49 is closed. The manipulator 61 therefore does not move the article C to be coated during the first explosion or in the event of a failure of the device, ie when the voltage value of the output of the power amplifier 39 is lower than the required value. When the output voltage of the power amplifier 39 corresponds to a predetermined value, that is, when the contact 50 of the electromagnetic relay 49 is closed, the manipulator 61
moves the article C to be painted along a predetermined path.

Although specific embodiments of the invention have been illustrated and described, it is not intended that the invention be limited to the embodiments described above, as various modifications will be apparent to those skilled in the art, but may be modified within the scope of the claims. It should be understood that this can be done.

[Brief explanation of the drawing]

1 is a functional diagram of the device according to the invention, FIG. 2 is a functional diagram of a control unit configured in the form of a master controller, and FIG. 3 is a functional diagram of another embodiment of the device according to the invention, including a manipulator. There is. 1... Explosion chamber, 2... Spark plug, 3
... Gas mixture supply system, 4 ... Powder supply system, 5 ... Control system, 6 ... Gas mixer, 7, 8, 9 ... ... Source of components of gas mixture, 10 ... Powder batch meter, 26 ... Control unit, 32 ... Feedback circuit, 33 ...
・Powder detector, 34...Signal converter, 45
...protection blind, 47 ...control circuit, 48 ...threshold element of control circuit,
61... Manipulator that moves the article to be painted.

Claims (1)

[Claims] 1. An explosion chamber 1 formed in the shape of a barrel with one end closed, a spark plug 2 for starting an explosion installed in the explosion chamber 1, and a source 7 of the components of the gas mixture. , 8, 9 and a mixer 6 communicating with the explosion chamber 1; a powder supply system 4 including a batch meter 18 communicating with the explosion chamber 1;
A control system 5 is provided, and this control system 5 includes a spark plug 2.
, a control unit 26 electrically connected to the gas mixture supply system 3 and the powder supply system 4, and a powder detector 33 installed at the open end of the explosion chamber 1 to detect powder in the explosion products.
a feedback circuit 32 with a control unit 26;
In such an explosive coating apparatus, the control system 5 further includes a signal converter 34 electrically connected to the powder detector 33 and converting the signal generated by the powder detector 33, the control system 5 further comprising A protective blind 45 is installed at the open end of the explosion chamber 1 behind the powder detector 33, and a control circuit 47 including a threshold element 48 is provided. A device characterized in that it is electrically connected to the signal converter 34 for converting the signal generated by the powder detector 33. 2 The control system 5 further includes a manipulator 61 for moving the article to be coated, which manipulator is connected to the threshold element 48 of the control circuit 47.
2. A device according to claim 1, which is connected to.