JP3019508U - Drum for bottom folding in bottom folding device of bag making machine - Google Patents

Abstract

(57) [Summary] [Structure] The body portion 2 of the bottom folding drum body 1 is notched to a required width in the cutting line direction to form a flat portion 2a, and a step portion 3 having a V-shaped cross section is formed at the front end portion in the rotational direction. Set up. A suction port 4 for suctioning at a predetermined timing is provided in the vicinity of the rear portion of the stepped portion 3 having the V-shaped cross section. A thin piece 17 for folding the envelope is fixed above the bottom folding drum body 1. Further, in front of the thin piece 17, a pressing roller 18 for contacting the body portion 2 of the bottom folding drum body 1 and rotating for attaching an envelope is provided. [Effect] Almost no bent part remains in the finished envelope. Further, the structure can be simplified and the device can be manufactured at low cost.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a bottom folding drum in a bottom folding device of a bag making machine.

[0002]

[Prior art]

 FIG. 8 shows an envelope whose bottom is folded by a rotary bag-making machine. The envelope A has a fold line B at the boundary between the body A'and the bottom sticking piece A "and at the same time, The glue C is applied to the surface of the portion A '.

The envelope A has a folding line B on the bottom portion by a bottom folding device, which has been conventionally performed as shown in FIGS. 9 and 10.

9 and 10, 101 is a folding blade, 102 is a glue blade, 103 is a bottom folding drum, 104 is a body portion of the bottom folding drum, and 105 is a slip formed on the body portion 104. Reference numeral 106 denotes a holding plate arranged in the slit, and the rotating folding blade 101 enters the slit 105 to slit the base of the bottom sticking piece A ″ of the envelope A (the boundary with the body A ′). The bending line B is pushed (FIG. 9) 105, and the holding plate 106 swings in the slit 105 in the rotation direction of the bottom folding drum to hold the bent portion (FIG. 10). It was attached.

However, when the nipping plate 106 strongly nips the portion of the envelope A that has entered the slit 105 as described above, the nipping plate 106 is bent at a substantially right angle as shown in FIG. As shown in Fig. 11, even when the product is completed, the bottom part of the product remains bent in a dogleg shape on one side.

[0006] Furthermore, such an envelope whose bottom part is bent is difficult to set in the printing machine when the printing company prints, and therefore, there is a demand for improvement in this point by the printing company.

In view of this, the present inventor previously devised a bottom folding drum (Japanese Patent Application No. 5-73316) shown in FIGS. 12 to 15. According to this, when the fold line is attached to the bottom of the envelope, it is possible to prevent a part of the envelope from being bent to one side when the envelope is completed.

In the bottom folding drum, a V-shaped groove 109 is provided at an appropriate position on the outer periphery of the body 108 along the width direction of the body 108, and the V-shaped groove 109 is formed. A bottom folding drum main body 107 having a suction port 110 for sucking at a predetermined timing in the rear portion in the vicinity of the rotation direction, and a rotation direction of the V-shaped groove 109 of the body 108 of the bottom folding drum main body 107. A support rod 111 that is provided in the front portion so as to be retractable and protrudes at a predetermined timing, a thin piece 112 for folding the envelope fixed above the bottom folding drum main body 107 at a right angle to the body portion 108, and from the thin piece 112. The bottom folding drum main body 107 includes a pressing roller 113 attached to an envelope, which is provided in a front portion of the bottom folding drum main body 107 in a rotation direction and rotates by contacting a body portion 108 of the bottom folding drum main body 107. It

Reference numeral 114 denotes a rotary shaft arranged below the V-shaped groove 109 in the body portion 108 so as to be parallel to the rotation axis of the bottom folding drum body 107. Is rotatably supported by a bearing provided on the side plate and one end 114a thereof is projected from the side plate.

Reference numeral 115 is a rocking lever having a base fixed to the end of the rotary shaft 114, and a roller 117 is rotatably mounted on the tip of the rotary shaft 114 with a shaft 116. Further, the rocking lever 115 is connected to the supporting rod 111, and the supporting rod 111 is moved in and out through the rocking of the rocking lever 115.

Reference numeral 118 is an arc-shaped cam plate which is brought into contact with the roller 117 at its peripheral edge and swings the swing lever 115 at a predetermined position. The cam plate 118 is fixed to the inside of the machine frame through a support so that the position facing the folding blade holder is slightly displaced from the position in the body rotation direction.

Reference numeral 119 denotes a rotary shaft of the bottom folding drum main body 107, which is rotatably supported by a machine frame with a bearing and is rotated at a predetermined speed by a required rotary drive mechanism.

In addition, 120 is a folding blade holder, 121 is a folding blade, 122 is a glue blade holder, and 123 is a glue blade.

The operation of the bottom folding drum is as follows. When the bottom folding drum main body 107 rotates from the state of FIG. 12 and the V-shaped groove 109 provided in the body portion 108 reaches a position directly above as shown in FIG. 13, the folding blade 121 and the glue blade 123 are synchronized. And then rotates, and the tip of the folding blade 121 enters the V-shaped groove 109. At this time, the front end side of the envelope is adsorbed by the suction port 110 of the body portion 108 of the bottom folding drum body 107. As a result, the base portion (the boundary with the body portion) of the bottom sticking piece of the envelope is pressed against the V-shaped groove 109, and the tip end side is slightly floated, that is, is bent in the reverse shape.

At this time, the supporting rod 111 projects from the body 108 of the bottom folding drum body 107 to raise the front end of the envelope and hits the back of the bent front end of the envelope. Thereafter, as shown in FIG. 14, the bottom folding drum body 107 further rotates, and when the leading end of the envelope hits a thin piece 112 provided above the bottom folding drum body 107 (FIG. 15), the envelope is folded back from the folding line portion. Be done. When the bottom folding drum main body 107 further rotates, the pressing roller 113 that contacts and rotates with the outer peripheral surface of the bottom folding drum main body 107 sticks the envelope sticking piece to the body portion.

[0016]

[Problems to be solved by the device]

 Such a bottom folding drum was able to achieve the intended purpose. However, when actually manufacturing it, the supporting rod 111 and the mechanism such as the cam plate 118 and the swinging lever 115 for projecting the supporting rod 111 at a predetermined timing are required, and the structure is complicated. There was a problem that the number of parts was large and the cost was high.

The present invention has been made in view of the above points, and it is possible to reduce the number of parts by simplifying the configuration by omitting a supporting rod and a complicated mechanism for projecting the supporting rod at a predetermined timing. To provide a bottom folding drum that realizes cost reduction.

[0018]

[Means for Solving the Problems]

 Thus, the gist of the present invention is that a flat portion is formed by cutting a desired width in the cutting line direction at an appropriate position on the outer periphery of the body portion, and a step portion having a L-shaped cross section is provided at the front end portion in the rotation direction. , A bottom folding drum body provided with a suction port for sucking at a predetermined timing in the rear portion in the rotation direction in the vicinity of the stepped portion of the V-shaped cross section, and above the bottom folding drum body at a right angle to the body portion. A bag-making device comprising a fixed thin piece for folding back an envelope, and a pressing roller for sticking an envelope, which is provided in front of the thin piece in the direction of rotation of the bottom folding drum body and rotates in contact with the body part of the bottom folding drum body. It is on the bottom folding drum in the machine bottom folding device.

[0019]

[Action]

 Next, the operation of the present invention will be described. When the bottom folding drum body rotates and the stepped part of the L-shaped cross section provided on the flat part of the body comes to the position directly above, the folding blade and glue blade rotate in synchronization, and the tip of the folding blade Hits the vertical wall of the step of the L-shaped cross section. At this time, the vicinity of the front end of the envelope is adsorbed by the suction port of the body of the bottom folding drum body (see FIG. 4). As a result, the base (the boundary with the body) of the bottom sticking piece of the envelope is sandwiched between the vertical wall of the stepped section of the L-shaped cross section and the folding blade, and bent at a substantially right angle to give a habit (Fig. reference). In this way, the base of the bottom sticking piece of the envelope is bent at a right angle, and the habit of raising the front end of the envelope is raised, so the support rod and However, the mechanism for projecting this at a predetermined timing can be omitted. Also, when the envelope is bent, the rear side (suction port side) of the bent portion is not pinched, so that there is no tendency for the envelope to bend.

Then, in this state, the bottom folding drum body further rotates as shown in FIG. 5, and when the leading end of the raised envelope hits a thin piece provided above the bottom folding drum body as shown in FIG. 6, The envelope is folded back from the folding line portion. Then, when the bottom folding drum body further rotates, the envelope sticking piece is attached to the body portion by the pressing roller that comes into contact with the outer peripheral surface of the bottom folding drum body and rotates.

[0021]

【Example】

 Embodiments of the present invention will be described below with reference to the drawings. 1 is a central longitudinal front view, FIG. 2 is a plan view of a body portion of a step portion having a L-shaped cross section, FIG. 3 is a side view, FIGS. 4 to 6 are operation explanatory diagrams, and FIG. It is an expanded sectional view.

In the figure, 1 is a bottom folding drum body. Reference numeral 2 is a body portion of the bottom folding drum body 1. In addition, a flat portion 2a is formed by notching the body portion 2 in a required width in the cutting line direction. Reference numeral 3 is a stepped portion having a V-shaped cross section, which is provided at the front end portion of the flat portion 2a in the rotational direction. Further, 3a is a vertical wall of the stepped portion 3 having the V-shaped cross section. Further, a required number of suction ports 4 are provided in a portion of the V-shaped cross section near the step portion 3. The suction port 4 is connected to a required suction device (not shown) so that suction is performed at a predetermined timing.

Reference numeral 5 denotes a rotary shaft of the bottom folding drum main body 1, which is rotatably supported by machine frames 6 and 6 with bearings 7 and 7 and is rotated at a predetermined speed by a rotary drive mechanism (not shown).

Reference numeral 8 denotes a thin piece which is fixed above the bottom folding drum body 1 at a right angle to the body portion 2 and is for folding the leading end portion of the envelope. Reference numeral 9 denotes a pressing roller that rotates in contact with the outer peripheral surface of the body portion 2 of the bottom folding drum body 1, and that sandwiches the envelope with the body portion 2 to attach the sticking piece of the envelope to the body portion. Is.

In addition, 10 is a folding blade holder, 11 is a folding blade, 12 is a glue blade holder, and 13 is a glue blade.

[0026]

[Effect of device]

 The present invention has the structure and operation as described above, and since the base of the bottom sticking piece of the envelope is bent at a right angle so that the front end of the envelope rises, the present inventors have previously devised it. It is possible to omit the supporting rod and a mechanism for projecting the supporting rod at a predetermined timing, which are required in the invention. Therefore, the structure can be simplified and the cost can be reduced. When the envelope is bent, the rear side (suction port side) of the bent portion is not pinched, so that there is no tendency for the envelope to bend.

[Brief description of drawings]

FIG. 1 is a central vertical front view of the present invention.

FIG. 2 is a plan view of a body portion of a step portion having a V-shaped cross section.

FIG. 3 is a side view.

FIG. 4 is an operation explanatory view in a state where a folding blade hits a stepped portion of a V-shaped cross section.

FIG. 5 is an operation explanatory view in a state where the folding blade is separated from the stepped portion of the V-shaped cross section.

FIG. 6 is an operation explanatory view in a state where the front end of the envelope hits a thin piece.

FIG. 7 is an enlarged sectional view of a portion P in FIG.

FIG. 8 is a plan view of the envelope before a fold line is formed.

FIG. 9 is an explanatory view of a conventional bottom folding drum, and is a cross-sectional view of a state in which a folding blade has entered a slit of a body portion.

FIG. 10 is an explanatory view of a conventional bottom folding drum, and is a cross-sectional view of a state where a sandwiching plate swings in a slit of a body portion.

FIG. 11 is a perspective view of an envelope in which folding lines are formed by a conventional bottom folding drum.

FIG. 12 is an explanatory diagram of a bottom folding drum devised earlier by the present inventor.

FIG. 13 is an operation explanatory view in a state where a folding blade is inserted in a V-shaped groove.

FIG. 14 is an operation explanatory view in a state where the folding blade is separated from the V-shaped groove.

FIG. 15 is an operation explanatory view in a state where the front end of the envelope hits a thin piece.

[Explanation of symbols]

 1 Bottom folding drum main body 2 Body part 2a Flat part 3 Step part of L-shaped cross section 4 Suction port 5 Rotating shaft 6 Machine frame 8 Thin piece 9 Pressing roller

Claims (1)

[Scope of utility model registration request] 1. A flat portion is formed by cutting a required width in a cutting line direction at a proper position on the outer periphery of the body portion, and a step portion having a L-shaped cross section is provided at a front end portion in the rotational direction, and the step portion having the L-shaped cross section is provided. And a bottom folding drum main body provided with a suction port for suctioning at a predetermined timing in the rear part in the rotation direction, and an envelope folding thin piece fixed at a right angle to the body above the bottom folding drum main body. A bottom folding device in a bottom folding device of a bag-making machine, which comprises a pressing roller for sticking envelopes, which is provided at a front portion of the bottom folding drum body in a rotational direction from the thin piece and rotates in contact with a body portion of the bottom folding drum body. Drums.