JPH0420828Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention relates to an improvement of a conveyor for conveying substrates that supports ceramic substrates, glass epoxy substrates, phenol substrates, etc., which are the base of electronic components, and conveys them through a furnace. It is.

(Conventional technology) When soldering components to the various circuit boards mentioned above, the components are mounted on the circuit board via solder, and then the circuit board is transported into a furnace where the solder is melted and joined. A method has been adopted to do so.
Conventionally, mesh belt conveyors have been widely used to transport such substrates, but in order to accommodate the diversification of substrate dimensions and to improve heating efficiency, link plates and belt conveyors for a pair of left and right conveyor chains have recently been used. A type of conveyor is used in which support rods whose protrusion amount can be adjusted by screwing into link pins or the like are attached facing inward, and both ends of the board are supported by the tips of these support rods. However, with such conveyors, if there is a dimensional difference in the width of the substrates, there is a risk that the substrates may get caught between the link plates during conveyance and be damaged, or may become unable to be conveyed and may overheat and catch fire. In order to do this, the support rods were made as short as possible, 2 to 3 mm, which resulted in drawbacks such as the substrates sometimes tilting or falling during transportation.

Further, as shown in FIG. 3, by attaching a pin head 22 to one of the conveyor chains 20 via a coil spring 21, the distance between the pin heads 22 and 23 changes according to the dimensional difference of the board 30. Conveyors are also used. However, in the case of the one shown in Fig. 3, when the coil spring 21 is run in the furnace, the coil spring 21 may be heated and become sag, or the fixing nuts of the pin heads 22 and 23 may become loose, causing the spring length to change.
Since the width between the link plates 25 and 25 is made larger than the width of the link plates 25, the conveyor chain 20 may meander, and when the error in the width dimension of the board 30 is taken into account, the board There were cases where the product fell or became unable to be transported.

(Problems to be solved by the invention) This invention solves the above-mentioned conventional problems and ensures that the substrates are transported inside the furnace without falling or being damaged even when the conveyor chain meanders. It was completed for the purpose of a conveyor for transporting substrates.

(Means for Solving the Problems) The present invention was developed to solve the above problems, and the present invention is to install pins for supporting substrates inside rollers supported between link plates of a conveyor chain running on rails. It is attached so that it can slide freely in the axial direction, and both ends of the board are supported between the board support pins of the other conveyor chain that is parallel to this conveyor chain. The invention is characterized in that an elastic pressing member is provided that is in contact with the pin and constantly presses the pin inward to a predetermined position.

(Example) Next, the present invention will be explained in detail with reference to an example shown in FIGS. 1 and 2.

Reference numerals 1 and 1 indicate a pair of left and right rails provided at both ends of the furnace, and 2 and 2 indicate a pair of left and right conveyor chains that run on these rails 1 and 1. This conveyor chain 2 is composed of link plates 3 and rollers 4 made of heat-resistant steel such as stainless steel. As shown in the figure, a pin 5 for supporting the substrate is attached to be slidable in the axial direction of the roller. These pins 5 pass through the roller 4 and have their outer ends protruding from the link plate 4 by about 2 to 3 mm, and their inner ends are cylindrical as shown in the figure, or have an appropriate shape. Attachments may also be provided. The pins 5 are preferably as thin as possible in order to heat the substrate 30 efficiently and uniformly, and the amount of inward protrusion is also preferably as short as possible.

In this embodiment, a cover 6 with an inverted L-shaped cross section is attached to the outside of the rails 1, 1 and extends to a position directly above the roller 4, and the above-mentioned slidable pin 5 is attached to the inner surface of one cover 6. A large number of elastic pressing members 7 are provided in contact with the end surface to constantly press the pin 5 inward to a predetermined position. This elastic pressing member 7 uses a leaf spring as shown in the figure.
It is also possible to use one that can press the end face of the pin 5 with a constant pressure using air pressure or the elastic force of a coil spring. The pressing force of the elastic pressing member 7 depends on the traveling speed of the conveyor chain 2 and the link plate 3.
, the size and weight of the substrate 30, etc., but it is sufficient as long as the position of the end surface of the pin 5 can always be maintained at a predetermined position.

In this embodiment, the cover 6 is used to block radiant heat inside the furnace and prevent deterioration of the leaf spring, making it possible to maintain a stable spring life over a long period of time. Since the rollers 4 are bent to prevent them from floating, the horizontality of the pair of conveyor chains 2, 2 can always be maintained correctly. Further, in this embodiment, the elastic pressing member 7 is attached to one of the conveyor chains 2, 2, but it can also be attached to both sides.

(Function) As shown in the figure, both ends of the substrate 30 are supported on the substrate support pins 5, 5 provided on the pair of conveyor chains 2, 2, respectively, and the substrate 30 is transported inside the furnace. However, heat treatment such as soldering is performed during this time, as in the conventional method.

However, in the present invention, the pin 5 is attached to the inside of the roller 4 of the conveyor chain 2 so as to be slidable in the roller axial direction, and the outer end face is pressed inward by the elastic pressing member 7. Even if the conveyor chain 2 meanderes during travel, the pins 5 slide relative to the rollers 4 and always maintain a constant position, so that the substrate 30 can always be supported correctly and transported stably. In this way, in the present invention, since the pins 5 do not oscillate horizontally, the distance between the pins 5 on both sides does not change due to a slight meandering of the conveyor chain 2, unlike in the conventional case, and the width of the board 30 is reduced. Even if there is some error in dimensions, the board 30 will not tilt or come off from the pins 5 during running. Furthermore, in the present invention, since the elastic pressing member 7 is provided outside the conveyor chain 2, it is not directly exposed to the radiant heat in the furnace, and especially if the cover 6 is provided as in the embodiment, deterioration due to the heat is further reduced. This makes it possible to reliably prevent this.

(Effects of the Invention) As is clear from the above explanation, the present invention is capable of reliably conveying the substrate without dropping or damaging the substrate even if the conveyor chain meandered while running. As it solves the problems of conventional conveyors for conveying substrates, its practical value is extremely large.

[Brief explanation of the drawing]

FIG. 1 is a partially cutaway plan view showing an embodiment of the present invention, FIG. 2 is a longitudinal sectional view thereof, and FIG. 3 is a longitudinal sectional view showing a conventional substrate conveyor. 1...Rail, 2...Conveyor chain, 3...
...Link plate, 4...Roller, 5...Pin,
7...Elastic pressing member.

Claims (1)

[Scope of utility model registration request] A board support pin 5 is attached to the inside of the roller 4 supported between the link plates 3 and 3 of the conveyor chain 2 running on the rail 1 so as to be slidable in the axial direction of the roller, and the other parallel to the conveyor chain 2 is attached. supporting both ends of the board 30 between the board support pins of the conveyor chain;
Further, the conveyor for conveying substrates is characterized in that an elastic pressing member 7 is provided on the outside of the conveyor chain 2, in contact with the end surface of the slidable pin 5, and constantly pressing the pin 5 inward to a predetermined position.