Screw quantitative feeding device

Abstract

To provide a screw quantitative feeding device which can shorten a feeding interval and reliably feeds out a predetermined number of screws using a brushless motor.SOLUTION: An alignment rail is provided to align screws, and a feeding mechanism is provided which is connected to the alignment rail and has a long hole that sends out the screws one by one, the feeding mechanism rotates 180 degrees to drop screws that are sent out into a hopper below, and a sensor is provided in its rotation path to count them, the mechanism then continues to rotate in one direction to send out screws, and when the sensor reaches a predetermined count, the feeding mechanism stops and the screws stored in the hopper are discharged.SELECTED DRAWING: Figure 10

Description

[Technical Field]

[0001] The present invention relates to a constant quantity screw feeder, and more particularly to a constant quantity screw feeder that reliably cuts out a predetermined number of screws. [Background technology]

[0002] In order to extract a fixed amount of screws S, it is necessary to separate the screws one by one and count them accurately. Conventionally, as shown in Patent Document 1, JP 2011-224712 A, particularly Figures 7(a) to (d) of the publication, screws S aligned in an alignment screw guide are rotated downward one by one into a screw receiving groove provided in a screw extraction disk, rotated approximately 140° by a motor and dropped down, and a sensor located midway detects the passage of the screws S and counts them. Explaining these conventional devices with reference to Figures 1 to 4 of the present application, a constant-quantity supply device 1 for screws S uses a DC motor 4a as a drive source to drive a disk 3a via an intermediate gear 34, and as shown in Figure 3, the rotation of the disk 3a is stopped by a stopper 33, and a spring 32 is fixed on the outer periphery of the cutting disk 3a, and when the DC motor 4a is not energized, it is pulled to the right in the figure by the force of the spring 32, and the stopper 33 is stopped in a state where it is pressed against one end of the elongated hole 31. When the DC motor 4a is energized, the disk 3a rotates to the right via the intermediate gear 34, and stops at a position where the stopper 33 hits the end of the groove 331 (the range 331 in which the stopper 33 can move).

[0003] As shown in Figure 4, the disk 3a has a slot 31 formed therein, and is integrally provided with a gear 35 and a stopper 33. When the screws S have finished dropping into the hopper 5 and the DC motor 4a is turned off, the force of the spring 32 causes the disk to return to its original position, completing its reciprocating motion. The above configuration limits the shortening of the cutting interval. Also, since the DC motor 4a is used, brush wear can sometimes require replacement of the motor. In addition, Patent Document 2, JP 2017-52615 A, uses a magnet to separate and count, but accurate counting is difficult because the number of components attracted varies depending on the weight, and it can only be used for components that can be attracted to a magnet. Furthermore, in Patent Document 3, JP 2019-69851 A, parts are placed in holes drilled in a rotating plate and separated and counted one by one, but this is not suitable for long parts such as screws, as they are likely to become tangled or get caught in the holes. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-224712 [Patent Document 2] Japanese Patent Application Publication No. 2017-52615 [Patent Document 3] Japanese Patent Application Publication No. 2019-69851 Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been made in consideration of the above-mentioned conventional problems, and provides a constant quantity screw feeder that can shorten the feeding interval and reliably feeds a predetermined number of screws using a brushless motor. [Means for solving the problem]

[0006] In order to solve the above problem, the present invention provides a screw constant quantity supply device in which the long hole 31 of the disk 3b is provided on the 180° opposite side, and the disk 3b is rotated by 180° using a stepping motor 4b, eliminating the need for the disk 3b to rotate in only one direction and return, thereby shortening the feeding interval. Also, to ensure that the direction of the elongated hole 31 of the disk 3b always stops at a position perpendicular to the alignment rail position, two slit plates are attached to the disk 3b at 180° each, and when it stops, an origin sensor attached to the bracket confirms that it is at the slit position. If the position is shifted, it rotates to the position of the slit and returns to the origin. Furthermore, since stepping motors do not have brushes that wear out, motor replacement is unnecessary and they can operate stably for long periods of time. [Effects of the Invention]

[0007] According to the screw constant volume supply device of the present invention, the cutting disk is rotated in one direction, so that the screw cutting speed can be increased, and as a result, the operating efficiency can be improved. In addition, by using a brushless stepping motor, motor replacement is no longer necessary and stable operation can be achieved for long periods of time. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a top view of a conventional thread cutting mechanism; [Figure 2] Cross section along line CC in Figure 1. [Figure 3] Enlarged view of part of Figure 2; [Figure 4] FIG. 4(a) is a perspective view of a conventional disk 3a, FIG. 4(b) is a front view of the disk 3a, FIG. 4(c) is a right side view of the disk 3a, and FIG. 4(d) is a rear view of the disk 3a. [Figure 5] 1 is a perspective view of a screw cutting mechanism according to an embodiment of the present invention, seen from diagonally above; [Figure 6] A partial enlarged view of the cutting mechanism in Fig. 5; [Figure 7] Top view of Figure 6; [Figure 8] 8(a) is a perspective view of the disk 3b, FIG. 8(b) is a front view of the disk 3b, FIG. 8(c) is a right side view of the disk 3b, FIG. 8(d) is a rear view of the disk 3b, [Figure 9] 1 is a top view of a screw feed mechanism of a constant-volume screw feeder according to an embodiment of the present invention; [Figure 10]A cross-sectional view taken along line BB in Figure 9. [Figure 11] FIG. 11(a) is a cross-sectional view of the state where the screw is transferred from the alignment rail to the disk 3b, FIG. 11(b) is a cross-sectional view of the state where the screw is moved by the disk 3b, and FIG. 11(c) is a cross-sectional view of the state where the screw falls from the disk 3b. [Figure 12] FIG. 10 is a perspective view of a state in which a fixed amount of screws stored in a hopper is being discharged.

[0009] A preferred embodiment of the screw supplying device of the present invention will be described with reference to the drawings. Figure 5 is a perspective view from diagonally above of the screw cutting mechanism of an embodiment of the present invention. When the constant volume supply device starts operating, screws S are fed into the feed port 11, and the screws S are then picked up from the bottom by the screw scooping section 12 and aligned horizontally on the alignment rail 2 with the head of the screw facing up, and the alignment rail 2 is vibrated back and forth by a vibration mechanism (not shown), causing the screws S to move on the alignment rail 2 in the direction of the disc 3b. This alignment and transport mechanism for the screws S is known from Japanese Patent Application Laid-Open No. 9-58847 and Japanese Patent Application Laid-Open No. 2010-208852, etc. The relationship between the alignment rail 2 and the cutting disc 3b in FIG. 5 is enlarged in an enlarged perspective view in FIG. 6 and a plan view in FIG. As shown in FIG. 8, the cutting disk 3b of this embodiment is significantly different from the conventional cutting disk 3a (FIG. 4).

[0010] As shown in Figure 8, the disk 3b has a slot 31 formed therein, which is integrally provided with a gear 35 and a slit 37. The slit 37 is positioned so that it is at the center of the origin sensor when the slot 31 is vertical. As shown in the cross-sectional side view of line BB in Figures 9 and 10, when a screw enters the cutting disk 3b, the stepping motor 4b rotates it 180° and stops, and the screw S is counted and dropped down, while the next screw S enters the disk 3b (one-way rotation). This will be explained using the progress diagrams of (a) to (c) in FIG.

[0011] In Figure 11(a), the origin sensor 41 and the slit 37 cause the disk 3b to always stop at a position where the slot 31 is vertical, and after a certain period of time, the disk 3b rotates 180° repeatedly. At this time, when the slot 31 of the disk 3b becomes vertical, the transported screw S enters the slot 31 in a hanging state and is held there. Next, in FIG. 11(b), the screw S rotates while being held in the long hole 31 of the disk 3b. As the head of the screw S passes through the transmission sensor during rotation, it is detected that one screw S has fallen, and the number is counted by a counter connected to the circuit board. Finally, in FIG. 11(c), as the disk 3b rotates 180°, the screw S falls downward due to its own weight and the centrifugal force of the disk 3b, and when the disk 3b has rotated 180°, the motor 4b stops. The origin sensor is a transmission sensor that monitors the position of the slit when stopped. If the slit 37 cannot be detected, it is determined that the position has shifted, and the origin return operation is performed by rotating the motor until the slit 37 is at the position of the origin sensor.

[0012] As shown in FIG. 5, the food is stored in the lower hopper 5, and the operation stops when the number of food items that has been dispensed is set in advance by the counter. When operation is stopped, as shown in Figure 12, there is a shutter 51 at the bottom of the hopper (storage section) 5 that slides back and forth and a lever 52 attached to the shutter, and the stored screws S can be discharged all at once by sliding back and opening the shutter 51 at the bottom of the storage section 5. The shutter 51 is equipped with a sensor (not shown), and when it detects that the screw S has been removed, it repeats the discharge operation for the next screw.

[0013] According to the device for supplying a constant amount of screws S of the embodiment of the present invention, the disk is rotated in one direction, so that the speed at which the screws S are cut out can be increased, and as a result, the operating efficiency can be improved. In addition, by using a brushless stepping motor, motor replacement is no longer necessary and stable operation can be achieved for long periods of time. [Explanation of symbols]

[0014] 1··Fixed screw supply device, 11··Screw inlet, 12··Screw scooping unit, 2··Alignment rail, 3a, 3b··Disc, 31··Slot, 32‥Spring, 33··Stopper, 331··Moving range of the stopper 34··Intermediate gear, 35··Gear, 37··Slit, 4a DC motor, 4b Stepping motor, 41··Sensor, 42··Counting sensor, 5··Hopper (storage section), 51··Shutter, 52··Removal lever.

Claims

[Claim 1] This device for supplying a fixed quantity of screws is provided with an alignment rail for aligning the screws, and an extrusion mechanism consisting of an extrusion disk connected to the alignment rail and having a long hole for extruding screws one by one, the extrusion mechanism rotates 180 degrees to drop the extruded screws into a hopper below, a sensor is provided in its rotation path to count the screws, and the extrusion mechanism continues to rotate in one direction to extrude screws, and when the sensor reaches a predetermined count number the extrusion mechanism stops and the screws stored in the hopper are discharged.

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