PIPE CRIMPING TOOL

A tube crimper includes a front crimper including a crimper body and multiple crimper wires arranged in a U shape and defining with the crimper body a U-shaped closed space therebetween, a die block mounted in the U-shaped closed space, and a hydraulic device having a pusher inserted through the crimper body of the front crimper and connected with the die block. After insertion of the tube and connector to be crimped into the U-shaped closed space, the hydraulic device is operated to move the pusher, causing the die block and the crimper wires to crimp the tube onto the connector.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to tube crimping technology, and more particularly to a tube crimper that uses a front crimper with crimper wires arranged in U shape to mate with a die block of a selected size for crimping tubes of different diameters.

2. Description of the Related Art

A conventional hydraulic crimper generally comprises a crimper body, a pair of C-shaped jaw holders arranged at a front side of the crimper body, and two jaws respectively mounted in respective jaw grooves in the C-shaped jaw holders for crimping a high-pressure tube. After insertion of the high-pressure tube to be crimped in between the two jaws in the two C-shaped jaw holders, the operating handle of the hydraulic crimper is biased, causing the two jaws to crimp the high-pressure tube. However, for crimping a high-pressure tube of a different diameter, the original pair of C-shaped jaw holders must be replaced by a pair of C-shaped jaw holders of a different size. Further, the tightening stress the mating end contact portions of the C-shaped jaw holders can impart is the weakest that cannot positively crimp the high-pressure tube.

SUMMARY OF THE INVENTION

The present invention has been accomplished under the circumstances in view. It is therefore the main object of the present invention to provide a tube crimper, which is practical for positively crimping tubes of different diameters, saving the cost.

To achieve this and other objects of the present invention, a tube crimper comprises a hydraulic device, a die block and a front crimper. The front crimper comprises a crimper body and a plurality of crimper wires. The crimper wires are arranged in a U shape for crimping, each comprising two opposite end portions respectively fastened to the crimper body. The crimper wires are disposed in parallel so that a U-shaped closed space is defined between the crimper wires and the crimper body. The hydraulic device comprises a pusher that is inserted through the crimper body of the front crimper and connected with the die block in the U-shaped closed space for allowing the crimper wires to be wound round the die block after insertion of the tube with the attached connector into the U-shaped closed space so that the hydraulic device is operable to move the die block and the crimper wires in crimping the tube onto the connector.

Further, the die block is detachably fastened to the crimper body of the front crimper so that different sizes of die blocks can be selectively used for crimping tubes of different diameters. Further, the crimper body of the front crimper comprises a support plate for supporting the loaded die block for positive crimping.

Further, each crimper wire defines an arc segment, two end portions respectively fastened to the crimper body, and two extension segments bilaterally connected between the arc segment and the end portions, where the diameter of the arc segment is larger than or equal to the distance between the two end portions so that the angle of the arc segment winding around the tube is larger than or equal to 180°. Thus, the tightening stress imparted by the crimper wires of the front crimper to the tube can extend over the mating contact area, avoiding stress attenuation and enhancing the crimping effect.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring toFIGS. 1-5, a tube crimper in accordance with the present invention is shown. The tube crimper comprises a hydraulic device1, a die block (2,2′) and a front crimper3.

The front crimper3comprises a crimper body31and a plurality of crimper wires32. In crimping, the crimper wires32are arranged in a U shape with respective opposite end portions323thereof affixed to the crimper body31. Further, these crimper wires32are arranged in parallel so that a U-shaped closed space33is formed between the crimper wires32and the crimper body31. In this embodiment, the end portions323of each crimper wires32are respectively wound around a respective post314in the crimper body31and fastened thereto.

The die block (2,2′) is mounted in the U-shaped closed space33, comprising a plurality of crimping ribs (21,21′). Further, the crimper wires32of the front crimper3wound round the die blocks (2,2′).

The hydraulic device1is fixedly connected to the crimper body31of the front crimper3, comprising a pusher11that is inserted through the crimper body31of the front crimper3and connected with the die block (2,2′). The tube4is inserted with the attached connector5into the U-shaped closed space33between the crimper wires32and the die block (2,2′), and then the hydraulic device1is operated to extend out the pusher11, forcing the die block (2,2′) to squeeze the tube4against the crimper wired32, and thus, the tube4is crimped and joined to the connector5.

The crimper body31of the front crimper3comprises a fixed block member311and a positioning block member312. The fixed block member311is connected with one end portion323of each crimper wire32. The positioning block member312is connected to the other end portion323of each crimper wire32. The positioning block member312and the fixed block member311are detachably connected together.

Referring toFIGS. 6 and 7andFIGS. 1-4again, the fixed block member311of the crimper body31comprises a positioning rib3111, and at least one locating hole3112located on the positioning rib3111. The positioning block member312comprises a coupling open chamber3121. In installation, the positioning rib3111of the fixed block member311is inserted into the coupling open chamber3121of the positioning block member312, and then a locating pin313is mounted in one locating hole3112of the positioning rib3111to fasten the fixed block member311and the positioning block member312together. In the embodiment shown inFIGS. 6 and 7, the positioning rib3111is configured to provide multiple locating holes3112. The locating pin313is selectively mounted in one of the locating holes3112to fasten the fixed block member311and the positioning block member312together.

In application, separate the positioning block member312from the fixed block member311of the crimper body31of the front crimper3, then insert the tube4with the attached connector5into the U-shaped closed space33between the crimper wires32and the die block (2,2′), and then attach the positioning block member312to the fixed block member311, and then fasten the locating pin313to the selected locating hole3112to lock the positioning block member312to the fixed block member311, holding the tube4in the U-shaped closed space33between the crimper wires32and the die block (2,2′), and then operate the hydraulic device1to extend out the pusher11in forcing the die block (2,2′) against the tube4and the crimper wires32, thereby crimping the tube4against the connector5. Thus, the tube4is deformed and fixedly secured to the connector5.

By means of selectively fastening the locating pin313to one of the locating hole3112, different sizes of die blocks (2,2′) can be selectively used according to the diameter of the tube4to be crimped. Thus, different sizes of die blocks (2,2′) can be selectively mated with the crimper wires32of the front crimper3to crimp tubes4of different diameters, saving the cost.

In addition to the crimping ribs (21,21′), the die block (2,2′) further comprises a plurality of guide grooves (22,22′) for accommodating and guiding the crimper wires32, avoiding displacement of the crimper wire32during crimping. Further, the crimper body31of the front crimper3further comprises a support plate34forwardly extended from a bottom side thereof for supporting the loaded die block (2,2′) for positive crimping.

When the crimper wires32are arranged in a U shape during the crimping operation, each crimper wire32defines an arc segment321, the aforesaid two end portions323that are fastened to the crimper body31, and two extension segments322bilaterally connected between the arc segment321and the end portions323, where the diameter of the arc segment321is larger than or equal to the distance between the two end portions323so that the angle of the arc segment321winding around the tube4is larger than or equal to 180°. Thus, the tightening stress imparted by the crimper wires32of the front crimper3to the tube4can extend over the mating contact area, avoiding stress attenuation and enhancing the crimping effect.