JP2663378B2 - Paper tube holding device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper tube holding device suitable for mounting, for example, at both ends of a paper tube for winding paper into a roll and holding the paper tube with its holding claws. .

[0002]

2. Description of the Related Art As a conventional paper tube holding device, for example, Japanese Utility Model Application Laid-Open No. 51454/1992 has an outer peripheral surface for supporting an inner surface of a paper tube and a rear flange for supporting an end surface of the paper tube. A casing having a plurality of window holes, a plurality of holding claws which fit into the window holes on the outer peripheral surface of the casing, project radially and press against the inner surface of the paper tube, a main body which fits on the inner surface of the casing, and a holding claw. A return mechanism for returning to the inside of the casing, wherein the main body is inclined and extended in the axial direction so as to be away from the center line of the main body as the holding claw is fitted and the bottom surface with which the inner end surface of the holding claw abuts goes rearward. A paper tube holding device provided with a holding claw guide groove formed of a groove has been proposed.

[0003] The return mechanism for returning the holding claws to the inside of the casing is contracted between a front end plate fixed to the front end of the casing and a spacer fixed in a stepped hole in the center of the main body. Using compression springs,
The casing is constantly biased forward with respect to the main body by the elasticity of the compression spring.

In this apparatus, after an outward flange provided at a rear end of a main body is attached to a drive shaft, the main body is moved forward or backward with respect to a casing together with the drive shaft to support and remove a paper tube. Things.

When the paper tube is supported by the paper tube holding device,
This is performed by fitting the outer peripheral surface of the casing to both ends of the inner surface of the paper tube, applying the end surface of the paper tube to the rear flange, and advancing the main body together with the drive shaft with respect to the casing. When the main body is advanced with respect to the casing, only the main body is advanced against the elasticity of the compression spring, and the casing and the holding claw are relatively moved rearward along the inclined bottom surface of the holding claw guide groove provided in the main body. Due to the action of the inclined bottom surface of the holding claw guide groove, the holding claw is moved radially outward to protrude from the window of the casing, and the outer surface of the holding claw bites into the inner surface of the paper tube, and at the same time, the end surface of the paper tube and the rear flange. The paper tube is held by contact.

When the paper tube is removed from the paper tube holding device, the main body is retracted with respect to the casing together with the drive shaft. When the main body is to be retracted with respect to the casing, only the main body is retracted with respect to the casing due to the return force of the compression spring, and the casing and the retaining claw are moved along the inclined bottom surface of the retaining claw guide groove. The holding claw fitted into the holding claw guide groove formed in the main body is forcibly pulled at this time, and the holding claw is moved radially inward to move the casing claw. The evacuation from the window hole releases the holding claw from the paper tube.

[0007] However, in the above-mentioned conventional paper tube holding device, no effort has been made in the forward and backward movement of the main body of the paper tube holding device for projecting and retracting the holding claws from the window of the casing. For this reason, the main body must be fixed to the rotary drive shaft for winding and the rotary drive shaft must be moved forward and backward with respect to the paper tube, so that insertion and removal of the paper tube holding device from the inner surface of the paper tube is troublesome. It was troublesome.

Further, when the main body is retracted from the casing holding the paper tube, the side of the holding claw is easily caught on the edge of the window hole of the casing, and furthermore, the compression spring is returned. If the claw of the holding claw digs into the inside of the paper tube in order to return the holding claw and the main body only by force, the main body is not stably retracted or the main body is retracted. Even in such a case, the return of the holding claw may be delayed without necessarily retreating the main body, or in some cases, the paper tube may be caught by the holding claw and may not come off. Therefore, the conventional paper tube holding device automates the attachment / detachment of the paper tube to / from the paper tube holding device because the operation of the main body at the time of retreat is not stable, and the responsiveness of the holding claw corresponding to the retraction of the main body is not good. Therefore, it is not suitable.

[0009]

SUMMARY OF THE INVENTION It is an object of the present invention to prevent a rotary drive shaft for winding from moving forward and backward with respect to a paper tube.
The expansion and contraction operations of the holding claws on the inner surface of the paper tube are performed immediately, and it is possible to reliably avoid the inconvenience that the paper tube is caught by the holding claws and does not come off. An object of the present invention is to provide a paper tube holding device suitable for automation.

[0010]

According to the present invention, there is provided a paper tube holding apparatus, comprising: an air cylinder body;
A piston fitted inside the air cylinder body so as to be movable back and forth in the axial direction, and a claw portion and a base portion provided at a front portion of the air cylinder body so as to be able to reciprocate in a radial direction of the air cylinder. A plurality of holding claws arranged along the circumferential direction, a taper portion having a smaller diameter toward the front end is formed near the front end of the piston, and the depth of the taper is along the inclination direction of the taper portion. A plurality of first guide grooves that are larger than the width are provided in the circumferential direction, a pressing body is provided at the rear end of the piston, and an annular portion is formed on the front surface of the pressing body. A first air chamber on the rear side of the pressing body of the piston, a second air chamber facing the annular portion on the front side of the pressing body of the piston, and a first air communicating with the first air chamber. A passage and a second air chamber communicating with the second air chamber. A plurality of second guide grooves are provided radially on the front end surface of the air cylinder body in the radial direction, and each of the plurality of holding claws is provided near a base of a claw portion of the holding claw. An inclined portion corresponding to the tapered portion of the piston is formed inside, and a first
And a second fitting is provided on the rear surface of the base of the holding claw.
A first fitting portion of each of the holding claws and the piston
Slides along the inner and outer widths of the first guide groove
The holding claw can be freely fitted and the second fitting portion of the holding claw can be moved forward.
Slidable in the second guide groove provided in the air cylinder body
It is characterized by being fitted to.

[0011]

After the paper tube is externally fitted to the claw portions of the holding claws arranged in the circumferential direction, air is injected from the first air passage of the air cylinder body. When air is injected from the first air passage of the air cylinder main body, the air is supplied to a first air chamber provided inside the air cylinder main body, and is fitted into the air cylinder main body by the air pressure of the first air chamber. The rear surface side of the pressed body of the piston is pressed to move the piston forward. When the piston is moved forward, a plurality of first guide grooves provided in the circumferential direction along the inclined direction of the tapered portion near the front end of the piston, and radially provided on the front end face of the air cylinder body in a radial direction. The pressing force directed forward from the piston is transmitted to each of the plurality of holding claws arranged in the circumferential direction while being slidably fitted to the second guide grooves. Each of the holding claws has a first fitting portion provided on an inclined portion corresponding to a tapered portion of the piston formed on the inner side near the base of the claw portion of the holding claw, and a first guide groove of the tapered portion of the piston. Are slidably fitted to the inner width and the width of the opening, respectively, so that a pressing force is applied to the first fitting portion from the tapered bottom surface of the first guide groove on the piston side, and the front of the piston is As the first fitting portion moves along the first guide groove of the piston from the distal end of the tapered portion at the front of the piston toward the base end of the tapered portion, A second fitting portion slidably fitted in a second guide groove provided on a front end surface of the cylinder body moves radially outward of the air cylinder body along the second guide groove. Is done. Thereby, each claw portion of the plurality of holding claws arranged in the circumferential direction is moved toward the radial outside of the air cylinder body, and each claw portion is expanded in the radial direction to press the inside of the paper tube. To hold the paper tube from inside. The air pressure applied to the first air chamber is maintained as it is.

When detaching the paper tube from the claw portion of the holding claw, air is injected from the second air passage of the air cylinder body. At the same time, the air pressure applied to the first air chamber is released. When air is injected from the second air passage of the air cylinder main body, the air is supplied to a second air chamber provided inside the air cylinder main body, and is fitted into the air cylinder main body by the air pressure of the second air chamber. The annular portion formed on the front side of the pressed body of the piston is pressed to move the piston backward. When the piston is moved rearward, the first fitting portions of the plurality of holding claws arranged in the circumferential direction are slidably fitted to the back width and the mouth width of the first guide groove provided in the piston. The first fitting portion of each holding claw is retracted by the mouth of the first guide groove, and the first fitting portion is moved by the first guide of the piston as the piston moves backward. At the same time as the piston is moved along the groove from the base end of the tapered part of the piston toward the tip of the front tapered part,
A second fitting portion slidably fitted in a second guide groove provided on a front end surface of the air cylinder body is directed radially inward of the air cylinder body along the second guide groove. Be moved. As a result, each claw portion of the plurality of holding claws arranged in the circumferential direction is moved inward in the radial direction of the air cylinder main body, and each claw portion is reduced in the radial direction, so that pressing toward the inside of the paper tube is reduced. The paper tube is released, and the paper tube can be pulled out from the claw portion of the holding claw.

As described above, it is possible to reliably advance the piston and retreat the piston by different air pressures without moving the rotary drive shaft for winding forward and backward with respect to the paper tube. At the same time as the reciprocating movement of the forward and backward movement of the piston, pressing and retraction are applied to the holding claws, enabling the holding claws to be expanded and contracted immediately, and the paper tube is caught by the holding claws and does not come off. Avoid surely.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a side view of a paper tube holding device 1 of the present invention, FIG. 2 is a front view of the paper surface holding device 1, and FIG.
FIG. 4 is a partial vertical sectional view of the paper tube holding device 1, and FIG. 4 is a rear view of the paper tube holding device 1.

The paper tube holding device 1 includes an air cylinder body 2 also serving as an apparatus body, a piston 3 fitted inside the air cylinder body 2 so as to be movable back and forth in the axial direction, and a front surface of the air cylinder body 2. A plurality of holding claws 4 are provided so as to be reciprocally movable in a radial direction of the air cylinder main body 2 and are arranged in a circumferential direction.

The air cylinder body 2 has a substantially cylindrical outer shape, and a front wall 6 having an opening 5 at the center is provided on the front side as shown in FIGS. Is
As shown in FIGS. 3 and 4, a rear wall 7 is provided, and an outer peripheral edge of the rear wall 7 is integrally formed with a mounting flange 8 having a diameter larger than the side peripheral surface of the air cylinder body 2.

The front wall 6 facing the outside of the air cylinder body 2
2 and 3, a plurality of second guide grooves 9 are provided radially in the radial direction. In the present embodiment, as shown in FIG. 2, five second guide grooves 9 are provided at respective apexes of a regular pentagon when viewed from the front. As shown in FIG. 5, the second guide groove 9
In the cross section, a concave portion 9b which protrudes from the groove bottom surface 9a to the left and right of the groove is formed, and the depth of the groove is larger than the width of the groove.

A hollow air chamber 10 is provided inside the air cylinder body 2, and the air chamber body 2 extends from the periphery of the opening 5 of the front wall 6 toward the rear side toward the air chamber 10. Up to the middle, a cylindrical peripheral wall 11 concentric with the axis
Are formed integrally with each other, and a piston rod through-hole 12 communicating with the air chamber 10 is formed in the interior surrounded by the peripheral wall 11. Further, as shown in FIG.
A first air passage 13 is provided in the center of the rear wall 7 in the axial direction so as to communicate with the rear side of the air chamber 10, while a second air passage 14 communicates with the front side of the air chamber 10 and is connected to the front wall 6 of the air cylinder body 2. 4, the connection port 16 of the first air passage 13 is provided at the center of the rear surface of the rear wall 7 while the connection port 1 of the second air passage 14 is provided at the center of the rear surface of the rear wall 7.
7 is provided on the side of the connection port 16 of the first air passage 13. Reference numeral 18 denotes a plurality of mounting bolt holes formed along the peripheral edge of the mounting flange 8 for fixing the paper tube holding device 1 to a rotation drive shaft (not shown).

As shown in FIG. 3, the piston 3 has a cylindrical piston rod 19 and a pressing body 20 formed integrally with the rear end of the piston rod 19. Near the front end of the piston rod 19, a tapered portion 21 having a smaller diameter toward the front end is formed, and extends along the inclination direction of the tapered portion 21 as shown in FIG. A plurality of first guide grooves 22 are formed in the circumferential direction. The first guide grooves 22 are formed with concave portions 22b that protrude from the groove bottom surface 22a to the left and right of the groove and have a greater depth than the mouth width. In this embodiment, as shown in FIG. 7, five first guide grooves 22 are provided.
Are disposed at respective apexes of a regular pentagon in a cross section orthogonal to the axial direction.

Pressing body 20 formed at the rear end of piston 3
Although not shown, it is circular in plan view and is formed to be larger in diameter than the piston rod 19, and a cylindrical rising wall 23 is formed on the periphery of the pressing body 20 toward the front, The rising wall 23 forms a concave annular portion 24 on the front surface of the pressing body 20.

As shown in FIG. 3, the piston 3 is moved from the air chamber 10 of the air cylinder body 2 to a piston rod 19.
With the tapered portion 21 at the tip protruding forward from the opening 5 of the front wall 6 of the air cylinder body 2, the piston rod 1
9 is slidably inserted concentrically into the piston rod through hole 12 of the air cylinder body 2 up to the proximal end of the air cylinder body 2, and the outer peripheral surface of the rising wall 23 of the pressing body 20 forms the side of the air chamber 10. The air chamber 10 is slidably fitted on the inner peripheral surface of the side wall 15 of the air cylinder body 2, and the air chamber 10 is divided into front and rear by a pressing body 20, and as shown in FIG. While one air chamber 10A is formed, as shown in FIG. 3, a second air chamber 24 facing the annular portion 24 on the front side of the pressing body 20 is formed.
An air chamber 10 </ b> B is formed, and the piston 3 is movable inside and outside the air cylinder body 2 in the axial direction.

FIG. 8 is a perspective view showing the holding claw 4 from the bottom side, FIG. 9 is a plan view of the holding claw 4, FIG. 10 is a side view of the holding claw 4, and FIG. FIG. 12 is a rear view of the nail 4, and FIG. 12 is a cross-sectional view taken along a line shown in FIG. The holding claws 4 are, as a general rule, air body 2
A claw base 25 radially disposed on the front surface of the air cylinder body 2, a columnar portion 26 protruding from one end of the claw base 25 toward the front in the front-rear direction of the air cylinder body 2, and an upper surface of the columnar portion 26 And a claw portion 27 formed at the bottom.

The claw base 25 of the holding claw 4 is shown in FIGS.
As shown in FIG. 2, cutout grooves 28, 2 cut out in the width direction of the claw base 25 are formed on right and left side surfaces which are rectangular parallelepiped and are orthogonal to the longitudinal direction corresponding to the radial direction of the air cylinder body 2.
8 are provided, and the bottom surface 28a of the groove 28 is provided.
The second fitting portions 29 projecting from the left and right sides of the claw base 25 are integrally provided on the back side of the claw base 25.

As shown in FIGS. 2 and 8, the columnar portion 26 protruding from one end of the claw base 25 toward the front has a substantially sector shape having an apex of an acute angle toward the bottom surface when viewed from the front. On the upper surface side of the columnar portion 26 which protrudes in a substantially arc shape when viewed from the front, a claw portion 27 formed of mountain-shaped irregularities as viewed from the front is formed up to the claw base 25 toward the longitudinal direction of the columnar portion 26. I have.

As shown in FIG. 2, the holding claw 4 has a top 26a of a columnar portion 26 including a substantially fan-shaped apex in a front view.
The air cylinder body 2 is disposed radially inward and cut diagonally from the middle of the top 26 a of the columnar portion 26 toward one end of the rear surface of the claw base 25 as shown in FIGS. 8 and 10 to 12. As a result, an inclined portion 30 corresponding to the tapered portion 21 of the piston rod 19 is formed, and is cut out in the width direction from the inclined portions 30 on both side surfaces of the columnar portion 26 intersecting at an acute angle toward the claw base 25. At the same time, notch grooves 31, 31 are provided in parallel with the inclined portion 30, respectively, and first fitting portions 32 projecting from the bottom surface 31a of the groove 31 to both left and right sides are provided integrally.

As shown in FIGS. 13 and 14, each of the holding claws 4 is slidably moved to the depth and mouth width of each of the five first guide grooves 22 provided in the tapered portion 21 of the piston rod 19. Each first fitting portion 32 provided on the holding claw 4 is fitted,
As shown in FIG. 1, the second fitting portions 29 provided on the holding claws 4 slidably fit in the depth width and the mouth width of the five second guide grooves 9 provided in the air cylinder body 2. Have been.
In addition, as shown in FIG.
And the front surface of the claw base 25 of the holding claw 4 are flush with each other.

Next, the operation of the paper tube holding device 1 will be described. First, the connection port 16 of the first air passage 13 and the connection port 17 of the second air passage 14 provided on the rear surface of the rear wall 7 of the air cylinder body 2 shown in FIG. ) To an air supply device (not shown). Reference numeral 33 denotes an O-ring. By switching the rotary switching valve, air injection and exhaust can be switched between two systems, respectively, and air injection into one air passage and air exhaust from the other air passage are performed simultaneously. In addition, the paper tube holding device 1 is used by inserting mounting bolts (not shown) into the mounting bolt holes 18 of the mounting flange 8 and fixing them to a rotation drive shaft (not shown) with the mounting bolts.

First, as shown in FIG.
When the pressing body 20 of the piston 3 retreats to the rear end of the first air chamber 10A on the rear surface side of the pressing body 20 and stops near the rear wall 7 of the air cylinder body 2, the piston 3 moves back and forth. It is assumed that it is in the retracted position in. At this time,
Second air chamber 10 facing annular portion 24 on the front side of pressing body 20
The air pressure is maintained while air is sealed in B.
The holding claw 4 is located at a reduced position near the center of the air cylinder body 2 in the radial direction.

When the paper tube is mounted and supported on the paper tube holding device 1, as shown in FIG. 3, the holding claw 4 at a reduced position near the center in the radial direction of the air cylinder main body 2 is used. The inner surface of the paper tube (not shown) is fitted around the columnar portion 26 of each holding claw 4 arranged in the circumferential direction, and the end surface of the paper tube is brought into contact with the end surface of the front wall 6 of the air cylinder body 2. After
Air is injected from the first air passage 13 of the air cylinder body 2.

When air is injected from the first air passage 13 of the air cylinder main body 2, air is supplied into a first air chamber 10A provided inside the air cylinder main body 2, and the first air chamber 1
The rear surface of the pressing body 20 of the piston 3 fitted inside the air cylinder main body 2 is pressed by the air pressure of 0 A,
Is moved forward in the axial direction.

When the piston 3 is moved forward, a plurality of first guide grooves 22 provided in the circumferential direction along the inclined direction of the tapered portion 21 near the front end of the piston 3 and the front wall 6 of the air cylinder body 2. A pressing force directed forward from the piston 3 is transmitted to each of the holding claws 4 slidably fitted in the second guide grooves 9 provided radially in the radial direction.

As shown in FIGS. 1 and 2, each of the holding claws 4 has the second fitting portion 29 fitted in the second guide groove 9 provided in the radial direction of the air cylinder body 2. The first fitting portions 32 formed on the left and right sides in parallel with the inclined portion 30 and protruding from the first guide groove 22 provided in the tapered portion 21 of the piston 3 cannot move in the axial direction. By being slidably fitted to the width and the mouth width, a pressing force is applied to the inclined portion 30 of the first fitting portion 32 from the tapered bottom surface 22a of the first guide groove 22 on the piston 3 side. As the piston 3 moves forward, the first fitting portion 32 slides along the first guide groove 22 of the piston,
At the same time as the holding claws 4 are relatively moved from the distal end of the tapered portion 21 of the piston 3 toward the base end of the tapered portion 21,
Each second fitting portion 29 is moved radially outward of the air cylinder body 2 along the second guide groove 9.

As a result, each claw portion 27 of the plurality of holding claws 4 arranged in the circumferential direction is moved outward in the radial direction of the air cylinder body 2, and each claw portion 27 is expanded in the radial direction. .

When the front surface of the annular portion 24 of the pressing body 20 of the piston 3 comes into contact with the distal end surface of the peripheral wall 11 formed at the center of the air cylinder body 2, the advance of the piston 3 is restricted and stopped. . At this point, each holding claw 4 is in the extended position, and each claw portion 2 of each holding claw 4 expanded in the radial direction.
7 holds the paper tube from the inside by pressing the inside of the paper tube. After the paper tube is held, the air pressure applied to the first air chamber is held as it is (see FIG. 15).

Next, when the paper tube is disengaged from the claw portion of the holding claw, air is injected from the second air passage 14 of the air cylinder body 2 and at the same time, air is removed from the first air chamber 13 to reduce the air pressure. To release.

When air is injected from the second air passage 14 of the air cylinder main body 2, air is supplied to a second air chamber 10B provided inside the air cylinder main body 2, and the second air chamber 1
An annular portion 24 formed on the front side of the pressing body 20 of the piston 3 fitted inside the air cylinder body 2 by the air pressure of 0B
Is pressed to move the piston 3 backward.

When the piston 3 is moved rearward, the first fitting portions 32 of the plurality of holding claws 4 arranged in the circumferential direction are adjusted to the depth and the width of the first guide groove 22 provided in the piston 3. Since each of them is slidably fitted, the first
The fitting portion 32 is retracted toward the piston 3 by both side edges of the mouth of the first guide groove 22, and the first fitting portion 32 is moved to the first guide groove 2 of the piston 3 as the piston 3 moves backward.
2, the respective holding claws 4 are relatively moved from the base end of the tapered portion 21 of the piston 3 toward the tip of the tapered portion 21, and at the same time, the respective second fitting portions of the respective holding claws 4 are moved. 29
Is moved radially inward of the air cylinder body 2 along the second guide groove 9.

As a result, each of the claw portions 27 of the plurality of holding claws 4 arranged in the circumferential direction is moved inward in the radial direction of the air cylinder body 2, and each of the claw portions 27 is reduced in the radial direction so that the paper is removed. The pressure on the inside of the tube is released, and the paper tube can be pulled out from the claw portion 27 of the holding claw 4. When the rear surface of the rising wall 23 of the pressing body 20 of the piston 3 comes into contact with a stopper portion 34 formed near the side wall of the rear wall 7 of the air cylinder body 2, the piston 3 is prevented from retreating and stops at the reduced position. (See FIG. 3) .

As described above, the forward movement of the piston 3 and the backward movement of the piston 3 can be reliably performed by different air pressures without moving the rotary drive shaft for winding forward and backward with respect to the paper tube. As a result, simultaneously with the reciprocation of the forward and backward movements of the piston 3, pressing and retraction are applied to the holding claws 4, so that the expansion and contraction operations of the holding claws 4 can be performed immediately. The inconvenience of not falling out is reliably avoided. Accordingly, in the paper tube holding device 1, since the operation of the piston 3 when the piston 3 advances and retreats is performed stably, and the responsiveness of the reduction operation of the holding claw 4 corresponding to the retraction of the piston 3 is good, the attachment and detachment of the paper tube is automated. In doing so, it may be suitable.

[0040]

According to the paper tube holding device of the present invention, the rear surface side of the pressing body of the piston fitted inside the air cylinder body is pressed by the air pressure of the first air chamber provided inside the air cylinder body. The piston is moved forward, and the air pressure of the second air chamber provided inside the air cylinder body presses the annular portion formed on the front side of the pressing body of the piston fitted inside the air cylinder body. Since the piston is moved rearward, it is possible to reliably advance and retract the piston by separate air pressures without moving the rotary drive shaft that performs winding forward and backward with respect to the paper tube.

Further, with the advance of the piston, the first fitting portion provided on the inclined portion of the holding claw is slidable in the depth and mouth width of the first guide groove of the tapered portion of the piston. By being fitted, a pressing force is applied to the first fitting portion from the tapered bottom surface of the first guide groove on the piston side, and the front portion of the piston is moved along the first guide groove of the piston. A second fitting portion is slidably fitted in a second guide groove provided in a front end surface of the air cylinder main body while being moved from a distal end of the tapered portion toward a base end of the tapered portion. ,
The air cylinder body is moved radially outward along the second guide groove, whereby each claw portion of the plurality of holding claws arranged in the circumferential direction is directed radially outward of the air cylinder body. Each claw portion is radially expanded, and with the retreat of the piston, the first fitting portions of the plurality of holding claws arranged in the circumferential direction are engaged with the first guide groove provided on the piston. Since each of the holding claws is slidably fitted to the back width and the mouth width, the first fitting portion of each holding claw is pulled in by the mouth portion of the first guide groove, and with the movement of the piston rearward,
The first fitting portion is moved along the first guide groove of the piston from near the base end of the tapered portion of the piston toward the tip of the tapered portion at the front, and is provided on the front end surface of the air cylinder body. The second fitting portion slidably fitted in the second guide groove is moved inward in the radial direction of the air cylinder body along the second guide groove, whereby the circumferential direction is reduced. Each claw portion of the plurality of holding claws disposed on the air cylinder is moved inward in the radial direction of the air cylinder body, and each claw portion is reduced in the radial direction. Since pressing and retraction are applied to the holding claw, the expansion and contraction operations of the holding claw can be performed immediately, and the inconvenience of the paper tube being caught by the holding claw and not coming out can be reliably avoided.

Therefore, the operation of the piston when the piston is moved forward and backward is performed stably, and the responsiveness of the reduction operation of the holding claw corresponding to the backward movement of the piston is good, which may be suitable for automatically attaching and detaching the paper tube.

[Brief description of the drawings]

FIG. 1 is a side view of a paper tube holding device according to an embodiment of the present invention.

FIG. 2 is a front view of the paper tube holding device of the embodiment.

FIG. 3 is a partial vertical cross-sectional view of the paper core holding device when the holding claw of the embodiment is reduced.

FIG. 4 is a rear view of the paper tube holding device of the embodiment.

FIG. 5 is a sectional view of a second guide groove of the air cylinder body.

FIG. 6 is a longitudinal sectional view of one side of a tapered portion of a piston.

FIG. 7 is a cross-sectional view of a tapered portion of a piston.

FIG. 8 is a perspective view of the holding claw shown from the bottom side.

FIG. 9 is a plan view of a holding claw.

FIG. 10 is a side view of a holding claw.

FIG. 11 is a rear view of the holding claw.

FIG. 12 is a sectional view taken along line AA of FIG. 10;

FIG. 13 is a cross-sectional view of a main part cut along line B in FIG. 3;

FIG. 14 is a cross-sectional view of a main part cut along line C in FIG. 3;

FIG. 15 is a partial vertical cross-sectional view of the paper core holding device when the holding claw of the embodiment is extended.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 paper tube holding device 2 air cylinder main body 3 piston 4 holding claw 5 opening 6 front wall 7 rear wall 8 mounting flange 9 second guide groove 9a groove bottom surface 9b recess 10 air chamber 11 peripheral wall 12 piston rod through hole 13 first air passage 14 second air passage 15 side wall 16 connection port 17 connection port 18 mounting bolt hole 19 piston rod 20 pressing body 21 taper section 22 first guide groove 22a groove bottom face 22b concave section 23 rising wall 24 annular section 25 claw base (base) 26 Columnar part 27 Claw part 28 Notch groove 29 Second fitting part 30 Inclined part 31 Notch groove 32 First fitting part 33 O-ring 34 Stopper part

Claims (1)

(57) [Claims] 1. An air cylinder main body, a piston fitted inside the air cylinder main body so as to be able to move back and forth in the axial direction, and a front part of the air cylinder main body provided so as to be reciprocally movable in a radial direction of the air cylinder. A plurality of holding claws having a claw portion and a base portion, and a plurality of holding claws arranged along a circumferential direction, and a taper portion having a smaller diameter toward the front end is formed near the front end of the piston, and the taper portion is formed. A plurality of first guide grooves having a depth greater than the mouth width are provided in the circumferential direction, a pressing body is provided at the rear end of the piston, and an annular portion is provided on the front surface of the pressing body. Forming a first air chamber inside the air cylinder main body on the rear side of the pressing body of the piston, a second air chamber facing the annular portion on the front side of the pressing body of the piston, First air passage communicating with the air chamber of And a second air passage communicating with the second air chamber, respectively, and a plurality of second guide grooves are radially provided on a front end surface of the air cylinder main body in a radial direction. Each of the holding claws has an inclined portion corresponding to the tapered portion of the piston inside the base of the claw portion of the holding claw, and a first fitting portion is provided on the inclined portion,
A second fitting portion is provided on the rear surface of the base of the holding claw,
A first guide in which a first fitting portion of a pawl is provided on the piston
When slidably fitted to the depth and mouth width of the groove,
A second fitting portion of the holding claw, the air cylinder body
A paper tube holding device slidably fitted in a second guide groove provided in the paper tube holding device.