Patent Application
20180003205
The disclosure relates to a pin, more particularly to a pull-out pin that is adapted to be removably inserted into two objects and couple the objects to each other.
A pin is a component commonly used in the industrial field, and has different structures and sizes according to different requirements. A pull-out pin is used for coupling at least two objects together with each of the objects having a pin hole for insertion of the pull-out pin thereinto. The objects may be mold bases or machine parts that need to be fixed at specific relative positions. For example, the pull-out pin may be used for installing an engine in a vehicle. The pull-out pin has a diameter slightly larger than that of the pin holes of the objects, and is formed with an operating hole extending along a central axis thereof . In use, a user needs to register the pin holes of the objects with each other, then tightly insert the pull-out pin into the registered pin holes for coupling the objects to each other. When separating the objects from each other, the user needs to insert a tool into the operating hole and turn the tool to remove the pull-out pin from the objects.
However, when the pin hole of one of the objects is a blind hole, air inside the blind pin hole may be hindered from flowing out during insertion of the pull-out pin thereinto since the pull-out pin fully obstructs the pin holes, and the air left between the pull-out pin and the blind pin hole may cause difficulty in installation of the pull-out pin. To solve this problem, the pull-out pin can be modified to be formed with a vent passage that permits the air to flow out therethrough. However, the objects coupled by the pull-out pin usually have adhesive substances accumulated inside the pin holes, such as grease. Thus, when the vent passage is consequently blocked by the grease, airflow through the vent passage will also be blocked.
Therefore, an object of the disclosure is to provide a pull-out pin that can alleviate the drawback associated with the prior art.
Accordingly, the pull-out pin is adapted to couple first and second objects to each other. Each of the first and second objects is formed with a pin hole. The pull-out pin is adapted to be removably and tightly inserted through the pin hole of the first object and into the pin hole of the second object. The pull-out pin includes a first end surface, a second end surface spaced apart from the first end surface, and an outer surrounding surface connected between the first and the second end surfaces and surrounding a central axis. The outer surrounding surface has a recessed surface portion that defines a vent groove extending from the first end surface in a direction toward the second end surface, and a helical groove that extends helically about the central axis from the first end surface toward the second end surface, and that intersects the vent groove.
Other features and advantages of the disclosure will become apparent in the following detailed description of the embodiment with reference to the accompanying drawings, of which:
Referring to
The pull-out pin 1 has a cylindrical shape, and has a central axis 10 (see
In this embodiment, the outer surrounding surface 13 of the pull-out pin 1 has a recessed surface portion 131, a connecting surface portion 132, a frustoconical surface portion 133 and a helical groove 134. The recessed surface portion 131 defines a vent groove extending from the first end surface 11 in a direction toward the second end surface 12. The connecting surface portion 132 extends from the first end surface 11 toward the second end surface 12, and is connected to opposite lateral sides of the recessed surface portion 131. The frustoconical surface portion 133 is disposed between the connecting surface portion 132 and the second end surface 12, and is connected to opposite lateral sides of the recessed surface portion 131. The frustoconcical surface portion 131 gradually converges toward the second end surface 12. The helical groove 134 extends helically about the central axis 10 from the first end surface 11 toward the second end surface 12, and intersects the vent groove. The helical groove has a first groove opening 135 formed at the first end surface 11, a second groove opening 136 formed at the second end surface 12, and a plurality of shallow groove portions 137 disposed between the first groove opening 135 and the second groove opening 136, and intersecting the vent groove. The helical groove 134 has a maximum depth (D1) (see
When the pull-out pin 1 is tightly inserted in the first and the second pin holes 211, 221, the recessed surface portion 131 cooperates with the first and the second inner surfaces 212, 222 to define a vent passage 138 (see
In this embodiment, when inserting the pull-out pin 1 into the first and the second pin holes 211, 221, air inside the first and the second pin holes 211, 221 can be expelled through the helical channel 134 and the vent passage 138 without interfering with the insertion of the pull-out pin 1.
However, if any one of the helical groove 134 and the vent passage 138 is blocked by grease, the air inside the first and the second pin holes 211, 221 can still be expelled through the other one of the helical groove 134 and the vent passage 138. Therefore, the structural design of the helical groove 134 and the vent passage 138 ensures that the air in the first and second pin holes 211, 221 can be expelled out of the first and second pin holes 211, 221, and that the pull-out pin 1 can be smoothly inserted into the first and second pin holes 211, 221.
Specifically, referring to
Therefore, by virtue of the intersections (i.e., the shallow groove portions 137) of the helical groove 134 and the vent groove defined by the recessed surface portion 131 of the outer surrounding surface 13, when the helical groove 134 and the vent passage 138 are blocked by multiple blocked points (A, B), the air can change route via the shallow groove portions 137 to flow out of the first and second pin holes 211, 212.
When removing the pull-out pin 1 from the first and second objects 21, 22, a user need only insert a tool (not shown) into the operating hole 14 from the open end 141 and rotate the tool to drive rotation of the pull-out pin 1 about the central axis 10, and at the same time, pull the pull-out pin 1 out of the first and second pin holes 211, 221.
As shown in
In the description above, for the purposes of explanation, numerous specific details have been set forth in order to provide a thorough understanding of the embodiments. It will be apparent, however, to one skilled in the art, that one or more other embodiments may be practiced without some of these specific details. It should also be appreciated that reference throughout this specification to “one embodiment,” “an embodiment,” an embodiment with an indication of an ordinal number and so forth means that a particular feature, structure, or characteristic may be included in the practice of the disclosure. It should be further appreciated that in the description, various features are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of various inventive aspects.
While the disclosure has been described in connection with what is considered the exemplary embodiment, it is understood that his disclosure is not limited to the disclosed embodiments but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.
