The invention herein pertains generally to a dimpler, and more particularly, to a dimpler including a ram driven by a compressed fluid to form a dimple in a pipe fitting for precise brazing purposes.
Pipes, tubes, fittings and other like objects, particularly of copper are usually joined by inserting one pipe having a small diameter with sufficient depth into a larger diameter pipe and then soldering or brazing the joined pipes, so a strong, durable joint is formed. Brazed joints are generally not as deep as soldered joints. U.S. Pat. Nos. 6,269,674 and 7,013,699 both disclose hand tools used for dimpling pipes to control the depth of insertion of the smaller pipe. Should a lot of pipes need to be joined in a timely manner, dimpling pipes or fittings by hand can be slow, difficult, laborious and inefficient. Also, hand tools may not provide an adjustment means for varying the depth of pipe insertion according to the particular dimpling requirements.
To address these and other disadvantages of prior art tools, the present invention was conceived and one of its objectives is to provide an automated device and method for dimpling pipes and pipe fittings for softer metals such as copper.
Another objective of the present invention is to provide a dimpler having a cylinder that can be driven by a supply of pressurized fluid.
Yet another objective of the present invention is to provide a dimpler with an adjustable rest for pressing dimples into a fitting at uniform distances from an end of the fitting and for varying the distance of the dimples from the end of the fitting.
Still another objective of the present invention is to provide a dimpler capable of dimpling pipes or fittings with greater wall thicknesses than conventional hand-held dimplers.
Yet still another objective is to provide a method of redimpling pipes and fittings for brazing at a lesser depth or length than previously dimpled for soldering.
Various other objectives and advantages of the present invention will become apparent to those skilled in the art as a more detailed description is set forth below.
The aforesaid and other objectives are realized by providing a dimpler that includes a frame supporting a cylinder that drives a ram toward a platen for pressing a dimple in a pipe, fitting or other like object. In the preferred embodiment of the dimpler, a handle controls the flow of pressurized fluid in a pneumatic cylinder by operating a valve in communication with entry and exit ports of the cylinder. Opening one port of the valve and closing the other directs the pressurized fluid into the cylinder to force the ram against, for example a fitting. Next, closing the one port and opening the other directs the pressurized fluid to atmosphere to release the ram and allow a spring to withdraw the ram from the fitting and into the ram housing. A threaded adjuster controls the rate of release of the fluid. A method of dimpling a pipe or fitting includes placing the fitting on the rest and operating the handle to open and close the ports to drive and withdraw the ram into and from the fitting.
For a better understanding of the invention and its operation, turning now to the drawings,
Preferably, frame 40 shown positioned schematically on table top 15 includes beam 49 fixedly spacing apart pillars 44, to form or approximate, with platen 52, an h-shaped structure mounted on base 19. Base 19 extends longitudinally parallel with or nearly parallel with the movement of ram 88, such as toward platen 52. Longitudinal axis L of rest 39 is seen in
Conventional cylinder 60 is preferably pneumatic and is fixed to pillar 44. Adjustment means 36 for changing the vertical position of T-shaped rest 39 in relation to platen 52 includes elongated opening or slot 31 defined by leg 37 of rest 39 and bolt 35. Rest 39 can therefore be clamped or tightened against pillar 46 with bolt 35 at the desired height. Shelf 33 of rest 39 is affixed by welding or the like to leg 37. Alternatively, or additionally, dimpler 12 can be constructed to include a threaded rod and nut, a lock pin system, a gear drive system or another device for vertically adjusting rest 39. Optional inverted U-shaped shroud 50, which is formed from metal or other suitable material is also shown in
In the preferred dimpler form, ram 88 reciprocates horizontally as shown in
Pressurized fluid supply takes the form of air pressurized by conventional air compressor C and stored in tank T in the preferred embodiment of the invention as shown schematically in
With reference primarily to
Depressing handle 29 opens the upper port and closes the lower port of valve port 20, which urges ram 88 toward platen 52 to press dimple 92 as pressurized fluid enters cylinder 60. Raising handle 29 closes the upper port and opens the lower port of valve 20 to allow ram 88 to retract from platen 52 by spring tension while directing pressurized fluid from cylinder 60. A coil spring (not shown) maintained within ram housing 89 assists in the retraction of ram 88. Threaded adjuster 53 (
The preferred method includes pressing three equally spaced apart dimples 92 (
The illustrations and examples provided herein are for explanatory purposes and are not intended to limit the scope of the appended claims.
| Number | Name | Date | Kind |
|---|---|---|---|
| 2375707 | Speller | May 1945 | A |
| 2438842 | Christensen | Mar 1948 | A |
| 2442949 | Fischer | Jun 1948 | A |
| 2592672 | Fischer | Apr 1952 | A |
| 2956148 | Shoebridge et al. | Oct 1960 | A |
| 2966195 | Roberts et al. | Dec 1960 | A |
| 6269674 | Sperko | Aug 2001 | B1 |
| 7013699 | Sperko | Mar 2006 | B1 |