Patent Application
20180178369
The present invention relates to a hand tool assembly, and more particularly, to a joint knife for concrete finish.
The conventional joint knife comprises a flexible blade with desired flex point for applying and smoothing compound and taping joints. The joint knife is ideal for spreading putty or joint compound. Generally, the blade is connected between two parts of the handle by a rivet.
However, the rivet tends to loose after being used for a period of time, this is mostly because the rivet extends through the knife only and contacts the knife by a circle instead by a face. Lateral force pushes the rivet frequently to cause the rivet to be loosened. In addition, the two parts of the handle are made by wood which cannot securely and firmly connected to the blade.
Another joint knife is an integral product which includes a plastic handle integrally formed with the blade during the processes of molding. Nevertheless, the handle has to be thick enough so as to provide a comfort griping feature to the users, the thicker the handle is, the longer time required to be cooled after molding. This makes the manufacturing cost be higher than other types of joint knives.
For those joint knives that require the blade directly connected with the handle, the connection becomes a main concern for the manufacturers. The blades are put in the molding set after they are polished, and the polished surface of the blades may be damaged by the molding set. Furthermore, the molding set for the conventional joint knives has to be cooled down quickly to accelerate efficiency of production, and the cooling agent is water, unfortunately, water may cause rusting to the blades.
The present invention intends to provide a hand tool assembly that eliminates the shortcomings mentioned above.
The present invention relates to a tool assembly and comprises a handle and a connection end which is connected to the handle by way of blow molding or ultra-sonic fusion. Alternatively, the connection end can be made by plastic injection molding, and the handle can be made by way of blow molding. The connection end has a slot defined axially therein. A blade includes a body and a toothed portion. The toothed portion of the blade is connected to the slot of the connection end. The toothed portion is inserted into the slot of the connection end when the connection end is molded by way of blow molding so that the toothed portion of the blade is connected to the slot of the connection end. The toothed portion has multiple teeth and each tooth includes an inclined edge tapered toward the downward toward the connection end.
Preferably, the toothed portion has multiple teeth and each tooth includes an inclined edge tapered toward the downward toward the connection end.
The present invention will become more apparent from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, a preferred embodiment in accordance with the present invention.
Referring to
The blade 3 has a body 31 and a toothed portion 32. The toothed portion 32 of the blade 3 is connected to the slot 13 of the connection end 1. Specifically, the toothed portion 32 has multiple teeth and each tooth includes an inclined edge tapered toward the downward toward the connection end 1. The toothed portion 32 is inserted into the slot 13 of the connection end 1 when the connection end 1 is molded by way of blow molding so that the toothed portion 32 of the blade 3 is connected to the slot 13 of the connection end 1. A chuck (not shown) is used to clamp the connection end 1 and the toothed portion of the blade 3, and the chuck is removed after the hand tool assembly is cooled down. Therefore, the toothed portion 32 is integrally connected to the inside of the slot 13.
The hand tool assembly 100 saves plastic material because the handle 2 and the connection end 1 are made by way of blow molding. The connection between the connection end 1 and the toothed portion 32 of the blade 3 is secured.
As shown in
The handle 2 has a protrusion 21 extending axially from one end thereof, and the protrusion 21 having a hooked portion 22 formed on the outer periphery thereof.
The connection end 1 includes a slot 13 defined axially in the first end thereof, and the second end of the connection end 1 is an open end. At least one rib 14 extends inward from the inner periphery of the open end of the connection end 1. In this embodiment, there are two ribs 14. The protrusion 21 of the handle 2 is inserted into the second end of the connection end 1 and the ribs 14 are engaged with the hooked portion 22.
A blade 3 has a body 31 and a toothed portion 32, wherein the toothed portion 32 of the blade 3 is connected to the slot 13 of the connection end 1. The toothed portion 32 has multiple teeth and each tooth includes an inclined edge tapered toward the downward toward the connection end 1.
As shown in
A blade 3 has a body 31 and a toothed portion 32. The toothed portion 32 of the blade 3 is connected to the slot 13 of the connection end 1. The toothed portion 32 has multiple teeth and each tooth includes an inclined edge tapered toward the downward toward the connection end 1.
As shown in
The hand tool assembly of the present invention is easily to make and saves plastic material. The connection between the blade 3, the connection end 1 and the handle 2 is secured so that the blade 3 does not disengaged from the connection end 1 or the handle 2 even if the blade 3 is applied by a large force.
While we have shown and described the embodiment in accordance with the present invention, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.
