Adhesive bonding and miscellaneous chemical manufacture – Methods – Surface bonding and/or assembly therefor
Patent
1978-12-24
1982-09-14
Wityshyn, Michael G.
Adhesive bonding and miscellaneous chemical manufacture
Methods
Surface bonding and/or assembly therefor
1563042, 1563046, 156359, 156366, 156378, 1563797, 1562742, 219 615, 219 66, 219 67, B29C 2702
Patent
active
043493971
DESCRIPTION:
BRIEF SUMMARY
The present invention relates to a method for connecting pipe components made of weldable plastic, by welding their ends by means of electrical resistance heating, and a device for performing the method.
When piping made of weldable plastic is being assembled considerable importance is attached to the method and the device used for interconnecting the piping components by electrical resistance heating. The expression "piping components" means pipe, adapting members of all types and fittings that are combined to form pipe systems and are to be interconnected. Connecting these piping components is a costly partial operation, and in addition determines the quality of the piping and for this reason has to be very reliably performed. Either sleeve joints, which constitute a part of the pipe components or welding sleeves that are separate from the pipe components and are installed on the ends of two components and connected to them, are used to connect the pipe components. A coil of resistance heating wire is placed in the overlapping areas of these connectors and this coil is heated electrically to make the connection, so that in the area around the coil the material of the overlapping ends of the piping components melts, thereby welding these components together. The thermal energy supplied through the coil is quantitatively regulated in such a manner that an optimum connection results, i.e., neither insufficient nor excessive heating is applied to the components that are to be connected. A device in which the adjustment of the thermal energy is made either manually or automatically is used for regulating the thermal energy according to the pipe components that are to be connected.
When welding the aforesaid connections by using such a device it is unavoidable, particularly in view of the fact that the connections are to be completed on a construction site, some of the connections will not be of sufficient quality. Usually this is because the amount of welding energy that is applied in making the connection is too small with regard to the type of connection and the prevailing environmental factors, e.g., the ambient temperature or a faulty connection, for example, loss of contact at a plug-in connector. In most instances this leads to the condition that although the connection is capable of withstanding mechanical loads it is not tight.
Thus, the problem of the present invention is to develop a method of the type described above, in such a manner that the largest number of influencing factors are at least approximately taken into consideration. According to the invention this problem is solved in that the square-law value of the welding voltage is formed and converted into a pulse frequency, the pulses being counted by a counter, the welding process being terminated once a nominal pulse count is reached. Thus, the welding energy supplied is very accurately maintained corresponding to the nominal welding energy, whilst also taking account of certain environmental influences, e.g. outside temperature, sleeve temperature, etc.
An additional safety feature with regard to the production of a welded joint is provided by a device which is suitable for performing the method according to the invention and which has an electrical circuit having a switch stage that can be switched off after metering the welding energy supply, whereby the switch stage incorporates means for its interruption if there is a failure of the power circuit.
An embodiment of the invention is illustrated in the accompanying drawing and is described hereinafter. The FIGURE-diagrammatically shows a device for connecting piping components made of weldable plastic in the form of a block diagram.
The device shown in the drawing is intended for making joints, particularly with welding sleeves but fundamentally there is no restriction regarding its use for welded joints of other types, e.g. sleeve joints. The device illustrated in the drawing is supplied with power by a power supply 1. The circuit is controlled by means of a switch stage 7. A welding sle
REFERENCES:
patent: 2393429 (1946-01-01), Swinehart
patent: 2423922 (1947-07-01), Arndt, Jr.
patent: 3506519 (1970-04-01), Blumenkranz
patent: 3788928 (1974-01-01), Wise
patent: 3822164 (1974-07-01), Guido et al.
patent: 3925139 (1975-12-01), Simmons
patent: 3996402 (1976-12-01), Sindt
LandOfFree
Method and device for connecting pipe components made of weldabl does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and device for connecting pipe components made of weldabl, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and device for connecting pipe components made of weldabl will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2153758