BRIEF DESCRIPTION OF THE DRAWINGS
FIGS. 1A and 1B show vertical section views showing a pin tip attachment structure according to a first embodiment of the invention, which represent a case that a pin tip is in a rising position and a case that it is in a falling position respectively;
FIGS. 2A, 2B and 2C show vertical section views showing a front-end portion of a pin to be attached with a pin tip in the structure, and a condition where a coil spring is attached to the end portion and a condition where a bush with collar is attached to the end portion, respectively;
FIGS. 3A and 3B show a front view and a plane view showing the bush with collar in the structure, respectively;
FIGS. 4A and 4B show vertical section views showing a pin tip attachment structure according to a second embodiment of the invention, which represent a case that a pin tip is in a rising position and a case that it is in a falling position respectively;
FIGS. 5A and 5B show vertical section views showing a pin tip attachment structure according to a third embodiment of the invention, which represent a case that a pin tip is in a rising position and a case that it is in a falling position respectively;
FIGS. 6A and 6B show vertical section views showing a pin tip attachment structure according to a fourth embodiment of the invention, which represent a case that a pin tip is in a rising position and a case that it is in a falling position respectively;
FIGS. 7A, 7B and 7C show vertical section views showing a different embodiment of the front end portion of the pin in the structures, which represent the front end portion of the pin to be attached with a pin tip, a condition where a coil spring is attached to the front end portion, and a condition where a bush with collar is attached to the front end portion, respectively;
FIGS. 8A and 8B show plane views showing a condition where the pin tip seizes an aluminum can, and a condition where it seizes an aluminum bottle, using partial cross sections, respectively;
FIG. 9 shows a schematic plane view showing a pin chain conveyor, and
FIGS. 10A, 10B and 10C show plane views showing usual pin tip attachment structures respectively.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
FIGS. 1A and 1B show a pin tip attachment structure according to a first embodiment of the invention, in which a reference 1 indicates a pin tip, reference 2 indicates a coil spring, reference 3 indicates a pin, reference 4 indicates a bush with collar, and reference 5 indicates a ring plate, respectively. The pin tip 1 is attached to the pin 3 in a stretchable and contractible manner by the coil spring 2 mounted on the pin 3. FIG. 1A shows a case that the coil spring 2 is stretched and the pin tip 1 is therefore in a rising position, and FIG. 1B shows a case that the coil spring 2 is compressed and deformed and the pin tip 1 is therefore in a falling position.
The pin tip 1 has a front end side formed in a semispherical shape, and has a cylindrical hole 1a opened at a lower end side in which the bush with collar 4 is fitted. At a front end portion 6 of the pin 3, a thinned small-diameter portion 7 is formed, and a large diameter portion 8 having the same size as size of the pin 3 is integrally formed with a front end of the pin, as shown in FIG. 2A. The ring plate 5 is attached to a lower side of the small-diameter portion 7, and as shown in FIG. 2B, the coil spring 2 is fitted with the periphery of the front-end portion 6 of the pin in an insertional manner and set on the ring plate 5. Then, as shown in FIG. 2C, the bush with collar 4 is attached retained by the large diameter portion 8 at the front end of the pin.
As shown in FIGS. 3A and 3B, the bush with collar 4 is in a configuration where a slit groove 9 is formed in a longitudinal direction, so that the inner diameter “d” of the groove can be expanded. In the bush with collar 4, a collar portion 11 is formed at a lower end of a cylindrical bush portion 10, and a hole 12 is formed through in an axial direction in the center. When the bush is fitted with the pin 3 in the insertional manner, first, the large diameter portion 8 of the front end of the pin is inserted into the hole 12, and at that time, the slit groove 9 is expanded by the large diameter portion 8 of the pin, thereby the inner diameter “d” of the hole 12 is expanded to be at least the outer diameter “D” of the large diameter portion 8 of the pin (refer to FIG. 2B) and fit with the large diameter portion 8 in the insertional manner.
Next, when the bush with collar 4 engaged with the large diameter portion 8 is further pushed down, the bush with collar 4 is fitted with the small diameter portion 7 in the insertional manner as shown in FIG. 2C. At that time, the slit groove 9 that has been expanded by the large diameter portion 8 is returned to have an original width so that the inner diameter “d” of the bush 4 becomes smaller than the outer diameter “D” of the large diameter portion 8. Then, the coil spring 2 is pinched between the ring plate 5 and the collar portion 11 and thus compressed. Therefore, the bush with collar 4 is forced up at any time by the coil spring 2, and an upper end 13 of the bush is seized to a lower end of the large diameter portion 8 of the pin. The bush with collar 4 that has been pushed down and temporarily fitted with the small diameter portion 7 in the insertional manner is not disengaged because the inner diameter “D” of the hole 12 is smaller than the outer diameter “D” of the large diameter portion of the front end of the pin.
The bush with collar 4 fitted with the pin 3 in the insertional manner in this way is fitted into a lower end of a cylindrical hole 1a of the pin tip 1, thereby the pin tip 1 is attached to the pin 3 (FIG. 1A). Then, when the pin tip 1 is pressed, the coil spring 2 is compressed and deformed, thereby the pin tip 1 falls, and the collar portion 11 of the bush with collar 4 is contacted to a base 14 using a step formed at a lower side of the small diameter portion 7 of the pin 3, thereby the pin tip 1 is stopped (refer to FIG. 1B). When pressing force is released, the coil spring 2 is stretched and the pin tip 1 rises as shown in FIG. 1A.
FIGS. 4A and 4B show a pin tip attachment structure according to a second embodiment of the invention. While a basic structure is same as in the case of the first embodiment, the pin 3 does not have the ring plate 5. Instead, a receiver base 18 for receiving the coil spring 2 is formed in the pin 3, and the coil spring 2 rests on the receiver base 18, and elastically supports the pin tip 1. FIG. 4A shows a case that the coil spring 2 is stretched and thus the pin tip 1 is in a rising position, and FIG. 4B shows a case that the coil spring 2 is compressed and deformed and thus the pin tip 1 is in a falling position.
FIGS. 5A and 5B show a pin tip attachment structure according to a third embodiment of the invention. While a basic structure is same as in the case of the first embodiment, the structure is different in that a structure of the bush with collar 4 is configured by separate pieces of a bush part and a collar part. That is, a lower end of the bush part is fitted in a concave portion provided in a top of the collar part so that the bush with collar 4 is configured. FIG. 5A shows a case that the coil spring 2 is stretched and thus the pin tip 1 is in a rising position, and FIG. 5B shows a case that the coil spring 2 is compressed and deformed and thus the pin tip 1 is in a falling position.
FIGS. 6A and 6B show a pin tip attachment structure according to a fourth embodiment of the invention. While a basic structure is same as in the case of the first embodiment, the structure is different in that a bush 19 to be fitted into the hole of the pin tip 1 is configured to have only the bush part without the collar part. Here, the upper end of the coil spring 2 directly contacts to the lower end of the pin tip 1 to support the pin tip 1. FIG. 6A shows a case that the coil spring 2 is stretched and thus the pin tip 1 is in a rising position, and FIG. 6B shows a case that the coil spring 2 is compressed and deformed and thus the pin tip 1 is in a falling position.
As shown in FIGS. 7A to 7C, the pin 3 can be attached with a sleeve configured by a separated component, without having the large diameter portion 8 (refer to FIG. 2A) integrally formed at the front-end portion. That is, as shown in FIG. 7A, the large diameter portion is not integrally formed at the front end of the pin, and a small diameter portion 7 extending to the front end is formed; and the coil spring 2 is set on the ring plate 5 attached to a lower side of the small diameter portion 7, and the bush with collar 4 is set on the coil spring 2 (FIG. 7B); then the bush with collar 4 is pushed down to compress and deform the coil spring 2, so that a sleeve 15 is pressed and fitted with the front end of the small diameter portion 7 (FIG. 7C). Here, the outer diameter of the sleeve 15 is made to be same as outer diameter of the large diameter portion 8, so that the upper end 13 of the bush with collar 4 contacts to a lower end of the sleeve 15 for retention. By using such a configuration, the bush with collar 4 need not have the slit groove.
It is obvious that the outer diameter of the sleeve 15 need not be made to be same as the outer diameter of the large diameter portion 8, and can be larger than the inner diameter “d” of the hole 12 of the bush with collar 4. The bush with collar 4, which is configured in a way of being not disengaged from the pin by press fitting of the sleeve 15 in this way, is then attached with the pin tip 1, resulting in the same configuration as in the first embodiment. Alternatively, a nut may be screwed with the pin instead of the sleeve 15. That is, when a screw thread portion is formed in the front end of the small diameter portion 7, and the nut is screwed with the screw thread portion, the bush with collar 4 contacts to the nut and thus not disengaged.
FIG. 8A shows a case that one aluminum can 16 is seized to a pin tip 1a, and FIG. 8B shows a case that one aluminum bottle 17 is seized to a pin tip 1b. The pin tip attachment structure of an embodiment of the invention can be used for conveying a container in a shape having a small port such as the aluminum bottle 17 shown in FIG. 8B, since the structure is configured to be usable even in the case that the pin tip 1 has a small diameter. However, the pin tip 1a having a large diameter as shown in FIG. 8A can be obviously attached by using the same structure.
Patent Application
20080041701
