Front edge folding mechanism of bag sewing machine and active edge folding method of front edge folding mechanism

Abstract

The front edge folding mechanism comprises the bag sewing machine which is arranged on a conveying belt in a positioned mode, an edge folding machine is arranged in front of the bag sewing machine and comprises an inner clamping plate and an outer clamping plate which are arranged in a front-back spaced mode, and a gap between the inner clamping plate and the outer clamping plate is a bag opening guide gap. A front guide wheel and a rear guide wheel are arranged on the two sides of the bag opening guide seam respectively along the bag opening guide seam in a front-back spaced mode through supports, and a belt with a certain width crosses the bag opening guide seam to be twisted by 180 degrees in a twisted mode to be wound on the front guide wheel and the rear guide wheel. The twist type 180-degree twist winding of the belt crossing the bag opening guide seam is obliquely downward twist winding, and the twist winding is that the side face, in the width direction, of the belt faces and is attached to the inner clamping plate to the rear guide wheel at the upper end of the bag opening guide seam by 180 degrees along with twist turning. And the packaging bag opening entering the flanging machine is fed into a bag sewing machine along with the twisted flanging of the belt.

Description

Technical Field

[0001] The invention relates to a front folding mechanism of a bag sewing machine and an active folding method thereof. Background Art

[0002] When packaging materials in woven bags (commonly known as snakeskin bags), the bag opening needs to be folded 180 degrees before being fed into a hemming machine for sewing to ensure a secure and leak-proof seal. The current folding method uses guide rods and twisted, shaped parts at the entry point of the hemming machine to gradually shift the bag opening from a vertical position to a 180-degree angle. This folding method causes friction between the front and back of the bag and the guide rods during the folding process. Furthermore, to accommodate longer bags, the hemming device must be longer. This folding mechanism has two drawbacks: first, frictional resistance can cause wrinkles at the bag opening, compromising seal quality, especially with softer bags; and second, the hemming mechanism is long and takes up too much space. Summary of the Invention

[0003] In response to the above problems, the purpose of the present invention is to provide a front folding mechanism of a bag sewing machine and an active folding method thereof, which adopts the active rotation of double rollers to fold, thereby improving the wrinkling phenomenon caused by friction and the problem of occupied equipment space in the existing folding mechanism.

[0004] In order to achieve the above object, the scheme of the present invention is: A front-end folding mechanism of a bag sewing machine includes a bag sewing machine positioned on a conveyor belt, the conveyor belt is used to convey the packaging bags to be sealed, the bag sewing machine is used to lock the edges of the bag openings, and a folding machine is provided before the bag sewing machine, the folding machine is used to fold the edge of the conveyed packaging bag 180 degrees and then send it into the bag sewing machine to lock the edges of the bag openings, wherein the folding machine includes two plywoods spaced apart in front and back, the two plywoods are respectively called inner plywood and outer plywood, the interval gap between the inner plywood and the outer plywood is the bag opening guide seam, and a front guide wheel and a rear guide wheel are respectively provided on both sides of the bag opening guide seam along the bag opening guide seam, with a distance between them being stretched in front and behind, and the front guide wheel faces the bag opening of the packaging bag entering the bag opening guide seam It is placed on the outer plywood side, and the rear guide wheel is placed on the inner plywood side before the bag sewing machine. A belt with a certain width is put on the front guide wheel and the rear guide wheel, wherein the belt put on the front guide wheel to face the bag opening of the packaging bag crosses the bag opening guide seam and is twisted 180 degrees in a twisted manner and wound backward from the rear side of the rear guide wheel to the front side of the front guide wheel. The twisted 180-degree twisting makes the rotation directions of the front guide wheel and the rear guide wheel just opposite, wherein: the twisted 180-degree twisting of the belt across the bag opening guide seam is a twisted winding obliquely downward, and the twisted winding is to make the width side of the belt turn 180 degrees at the upper end of the bag opening guide seam and face and stick to the inner plywood to the rear guide wheel. A motor drives the front guide wheel or the rear guide wheel to rotate.

[0005] The solution is further as follows: the rear guide wheel is driven to rotate by a motor and is called a driving wheel, and the front guide wheel is a driven wheel, wherein: the axial bottom end of the front guide wheel is higher than or equal to the pocket guide seam on the outer splint side, so that the width direction of the twisted and wrapped belt is higher than the pocket guide seam on the outside of the pocket guide seam; the axial upper end of the rear guide wheel is higher than or level with the pocket guide seam on the inner splint side, so that the upper end of the belt sleeved on the rear guide wheel is flush with the pocket guide seam.

[0006] A further solution is that the rotation speed of the belt driven by the motor is greater than or equal to the speed at which the conveyor belt conveys the packaging bags.

[0007] The solution is further that the front guide wheel and the rear guide wheel are separated one after the other so that the belt is twisted and turned 180 degrees to face the inner splint with a length of not less than 200 mm.

[0008] A front-mounted active hemming method for a bag sewing machine is an active hemming method based on the front-mounted hemming mechanism of the bag sewing machine, wherein: the rear guide wheel is driven to rotate by a motor, and the method comprises: Step 1: Use the bracket to adjust the distance and height of the front guide wheel and the rear guide wheel along the bag opening guide seam so that the width direction of the twisted belt is higher than the bag opening guide seam on the outside of the bag opening guide seam; the axial upper end of the rear guide wheel is higher than or flush with the bag opening guide seam on the inner splint side so that the upper end of the belt on the rear guide wheel is flush with the bag opening guide seam; The belt that is higher than the guide seam of the bag opening is used to stick to the bag opening of the packaging bag that moves over and enters the guide seam of the bag opening; The upper end of the belt on the rear guide wheel side is flush with the bag opening guide seam. It is used to carry the bag opening with the belt and twist it 180 degrees to face the inner plywood to the rear guide wheel, and then send the folded bag opening out to the bag sewing machine. Step 2: Start the conveyor belt and adjust the motor to drive the belt to rotate at a speed greater than or equal to the speed at which the conveyor belt transmits the packaging bag; Step 3: Place the packaging bag to be sealed on the conveyor belt and start the folding machine and bag sewing machine.

[0009] The solution is further that: the method further includes: when wrinkles appear on the folded edge, adjusting the relative rotation speed of the belt driven by the motor (7) and the transmission belt to eliminate the wrinkles.

[0010] The beneficial effects of the present invention are as follows: the folding mechanism of the present invention adopts a power-active gradual change method, twisting a belt by a certain angle through two guide wheels, so that the woven bag opening gradually turns 180 degrees along with the twisted surface of the belt and enters the bag sewing machine. At the same time, one of the guide wheels is installed on the output shaft of the motor, so that the belt has power transmission, so that the surface of the rear side of the woven bag that contacts the belt has dynamic friction, so that the woven bag opening that needs to be folded is consistent with the speed of the conveyor and the stroke is synchronized. Folding while moving, the woven bag opening is kept in a neat state and enters the bag sewing machine, ensuring that the woven bag opening is wrinkle-free during the sewing process. It can be used on semi-automatic and automatic packaging equipment. The design of the present invention is ingenious, occupies little space, has a long service life, and has a wide range of applications.

[0011] The present invention will be described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a schematic structural diagram of the present invention; Figure 2 This is a schematic diagram of the packaging bag end side of the structure of the present invention; Figure 3 This is a schematic diagram of the packaging bag end side of the structure of the present invention; Figure 4 This is a schematic diagram of the axial side structure of the present invention in one direction; Figure 5 This is a schematic diagram of the axial structure of another direction of the present invention; Figure 6 It is a schematic structural diagram of the present invention without two splints. DETAILED DESCRIPTION

[0013] Example 1: A front folding mechanism for a bag sewing machine, such as Figures 1 to 6As shown, the front folding mechanism of the bag sewing machine includes a bag sewing machine 2 positioned on a conveyor belt 1, the conveyor belt 1 is used to convey the packaging bag 3 to be sealed on the packaging line, the bag sewing machine 2 is used to lock the edge of the bag mouth 301, and a folding machine 4 is provided before the bag inlet of the bag sewing machine 2. The folding machine 4 is used to fold the edge of the bag mouth 301 conveyed by the bag sewing machine 2 by 180 degrees and then send it into the bag sewing machine 2 to lock the edge of the bag mouth 301; wherein: the folding machine 4 includes two plywood 401 spaced apart in front and back, and the two plywood are respectively called inner plywood 40 1-1 and outer splint 401-2, the inner splint 401-1 and the outer splint 401-2 are in a 90-degree folded shape for easy installation. The mounting bracket is omitted in the figure. The interval gap between the inner splint 401-1 and the outer splint 401-2 is the bag guide seam 402. On both sides of the bag guide seam 402, a front guide wheel 403 and a rear guide wheel 404 are respectively provided along the bag guide seam 402, one in front and one behind, through the bracket 5. The front guide wheel 403 faces the end face of the bag opening 301 of the packaging bag entering the bag guide seam 402 and is placed on the outside of the outer splint 401-2 side. The rear guide wheel 404 is placed on the outside of the inner plywood 401-1 before the bag sewing machine 2, and a belt 6 with a certain width is put on the front guide wheel 403 and the rear guide wheel 404. The belt 6 on the front guide wheel 403 facing the bag opening 301 crosses the bag opening guide seam 402 and twists 180 degrees in a twisted manner, then winds backward from the rear side of the rear guide wheel 404 and forward to the rear side of the front guide wheel 403. The twisted 180 degrees in a twisted manner makes the rotation directions of the front guide wheel 403 and the rear guide wheel 404 just opposite, wherein: the belt 6 crosses the bag opening guide seam 402 The twisted 180-degree twist winding of 2 is a twist winding in an oblique downward direction. The oblique downward twist winding is to make one side of the belt width turn 180 degrees at the upper end of the bag guide seam 402 and face and close to the inner plywood 401-1 to the rear guide wheel 404. A motor 7 drives the front guide wheel 403 or the rear guide wheel 404 to rotate; the bracket 5 has an up and down and front and back position adjustment mechanism for the front guide wheel 403 and the rear guide wheel 404, which is not shown in the figure. The hole for installing the guide wheel shaft is a long hole, and the guide wheel adjusts the up and down position on the guide wheel shaft through the upper and lower limit switches.

[0014] In the embodiment, since the rear guide wheel 404 is the main force-bearing guide wheel, the rear guide wheel 404 is driven by the motor 7 to rotate and is called the driving wheel, and the front guide wheel 403 is the driven wheel, wherein: the axial bottom end of the front guide wheel 403 is higher than or equal to the upper end of the bag guide seam 402 on the side of the outer splint 401-2, so that the width direction of the twisted winding belt is higher than the bag guide seam 402 on the outside of the bag guide seam 402; the axial upper end of the rear guide wheel 404 is higher than or level with the upper end of the bag guide seam 402 on the side of the inner splint 401-1, so that the upper end of the belt sleeved on the rear guide wheel 404 is flush with the upper end of the bag guide seam 402.

[0015] In order to prevent wrinkles from occurring after folding, the motor 7 drives the belt 6 to rotate at a speed slightly greater than or equal to the speed at which the conveyor belt 1 conveys the packaging bag. The motor 7 can be adjusted to eliminate wrinkles.

[0016] In the embodiment, the distance between the front guide wheel 403 and the rear guide wheel 404 is such that the belt 6 twists and turns 180 degrees to face the inner plywood 401-1 and has a certain length, which may be about 100 mm. For better effect, the distance in this embodiment is not less than 200 mm.

[0017] Example 2: A front-mounted active hemming method for a bag sewing machine is an active hemming method based on the front-mounted hemming mechanism of the bag sewing machine described in Example 1. The contents of Example 1 are applicable to this embodiment, wherein: the rear guide wheel 404 is driven to rotate by the motor 7, and the method includes: Step 1: Use the bracket 5 to adjust the distance and height of the front guide wheel 403 and the rear guide wheel 404 along the bag opening guide seam 402, so that the width direction of the twisted belt is higher than the bag opening guide seam 402 on the outside of the bag opening guide seam 402; the axial upper end of the rear guide wheel 404 is higher than or flush with the bag opening guide seam 402 on the side of the inner clamping plate 401-1, so that the upper end of the belt on the rear guide wheel 404 is flush with the bag opening guide seam 402; The belt that is higher than the bag opening guide seam 402 is used to stick to the bag opening 301 of the packaging bag that moves into the bag opening guide seam 402; The upper end of the belt 6 on the rear guide wheel 404 side is flush with the bag opening guide seam 402. The belt 6 is used to carry the bag opening 301 of the packaging bag and twist it 180 degrees to face the inner clamping plate 401-1 to the rear guide wheel 404, and then send the folded bag opening 301 to the bag sewing machine 2. Step 2: Start the conveyor belt 1 and adjust the rotation speed of the motor 7 to be greater than or equal to the speed at which the conveyor belt 1 transmits the packaging bag; Step 3: Place the packaging bag 3 to be sealed on the conveyor belt 1, start the folding machine 4 and the bag sewing machine 2, and when wrinkles appear on the folded edge, adjust the relative rotation speed of the belt 6 driven by the motor 7 and the conveyor belt 1 to eliminate the wrinkles.

[0018] The above-mentioned front-end folding mechanism of the bag sewing machine and the embodiment of the active folding method thereof twist a belt by a certain angle through two guide wheels, so that the opening of the woven bag gradually turns 180 degrees along with the twisted surface of the belt and enters the bag sewing machine. At the same time, one of the guide wheels is installed on the output shaft of the motor, so that the belt has power transmission. In this way, the surface of the woven bag's rear side in contact with the belt has dynamic friction, so that the woven bag opening that needs to be folded is consistent with the speed of the conveyor and the travel is synchronized. Folding while moving, the woven bag opening is kept in a neat state before entering the bag sewing machine, ensuring that the woven bag opening is wrinkle-free during the sewing process. It can be used on semi-automatic and automated packaging equipment.

Claims

1. A front-end folding mechanism for a bag sewing machine, comprising a bag sewing machine (2) positioned on a conveyor belt (1), the conveyor belt (1) being used to convey packaging bags (3) to be sealed, the bag sewing machine (2) being used to lock the edges of the bag openings (301) of the packaging bags, a folding machine (4) being provided before the bag sewing machine (2), the folding machine (4) being used to fold the edges of the conveyed packaging bags (301) by 180 degrees and then convey the edges into the bag sewing machine (2) to lock the edges of the bag openings (301) of the packaging bags, and characterized in that: The folding machine (4) comprises two splints (401) spaced apart from each other in front and back, the two splints being respectively called an inner splint (401-1) and an outer splint (401-2), the gap between the inner splint (401-1) and the outer splint (401-2) being a bag opening guide seam (402), and a front guide wheel (403) and a rear guide wheel (404) being respectively arranged on both sides of the bag opening guide seam (402) along the bag opening guide seam (402) at a distance from each other through a bracket (5), the front guide wheel (403) being arranged on the side of the outer splint (401-2) facing the bag opening (301) of the packaging bag entering the bag opening guide seam (402), and the rear guide wheel (404) being arranged on the side of the inner splint (401-1) before the bag sewing machine (2), and a belt (6) having a certain width being sleeved on the front guide wheel (403) and the rear guide wheel (404). 4), wherein a belt (6) mounted on a front guide wheel (403) and directed toward the bag opening (301) of the packaging bag is twisted 180 degrees across the bag opening guide seam (402) and wound backward from the rear side of the rear guide wheel (404) and forward to the rear side of the front guide wheel (403), and the twisted 180 degrees winding makes the rotation directions of the front guide wheel (403) and the rear guide wheel (404) just opposite, wherein: the twisted 180 degrees winding of the belt (6) across the bag opening guide seam (402) is a twisted winding in an oblique downward direction, and the twisted winding is such that the width side of the belt is twisted 180 degrees at the upper end of the bag opening guide seam (402) and wound along the inner splint (401-1) to the rear guide wheel (404), and a motor (7) drives the front guide wheel (403) or the rear guide wheel (404) to rotate.

2. The front folding mechanism of the bag sewing machine according to claim 1, characterized in that: The rear guide wheel (404) is driven to rotate by the motor (7) and is called the driving wheel, and the front guide wheel (403) is the driven wheel, wherein: the axial bottom end of the front guide wheel (403) is higher than or equal to the bag opening guide seam (402) on the side of the outer clamping plate (401-2), so that the width direction of the twisted belt is higher than the bag opening guide seam (402) on the outside of the bag opening guide seam (402); the axial upper end of the rear guide wheel (404) is higher than or equal to the bag opening guide seam (402) on the side of the inner clamping plate (401-1), so that the upper end of the belt mounted on the rear guide wheel (404) is flush with the bag opening guide seam (402).

3. The front folding mechanism of the bag sewing machine according to claim 1, characterized in that: The motor (7) drives the belt to rotate at a speed greater than or equal to the speed at which the conveyor belt (1) conveys the packaging bag.

4. The front folding mechanism of the bag sewing machine according to claim 1, characterized in that: The front guide wheel (403) and the rear guide wheel (404) are spaced apart in front of each other so that the belt (6) twists and turns 180 degrees to face the inner clamping plate (401-1) by a distance of not less than 200 mm.

5. A method for active front-end hemming of a bag sewing machine, which is based on the active hemming method of the front-end hemming mechanism of the bag sewing machine according to claim 1, wherein: The rear guide wheel (404) is driven to rotate by a motor (7), and is characterized in that the method comprises: Step 1: Adjust the distance and height of the front guide wheel (403) and the rear guide wheel (404) along the bag opening guide seam (402) by using the bracket (5) so that the width direction of the twisted belt is higher than the bag opening guide seam (402) on the outside of the bag opening guide seam (402); the axial upper end of the rear guide wheel (404) is higher than or flush with the bag opening guide seam (402) on the side of the inner clamping plate (401-1) so that the upper end of the belt mounted on the rear guide wheel (404) is flush with the bag opening guide seam (402); The belt is higher than the bag opening guide seam (402) and is used to stick to the bag opening (301) of the packaging bag that moves into the bag opening guide seam (402); The upper end of the belt (6) on the side of the rear guide wheel (404) is flush with the bag opening guide seam (402), and is used to carry the bag opening (301) of the packaging bag with the belt (6) and twist it 180 degrees to face the inner splint (401-1) to the rear guide wheel (404), and then send the folded bag opening (301) of the packaging bag out to guide it to the bag sewing machine (2); Step 2: Start the conveyor belt (1), and adjust the motor (7) to drive the belt to rotate at a speed greater than or equal to the speed at which the conveyor belt (1) transmits the packaging bag; Step 3: Place the packaging bag (3) to be sealed on the conveyor belt (1), and start the folding machine (4) and the bag sewing machine (2).

6. The method according to claim 5, characterized in that The method further comprises: when wrinkles appear on the folded edge, adjusting the relative rotation speed of the belt driven by the motor (7) and the transmission belt to eliminate the wrinkles.

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