JPH04227883A - Adhesive coating device - Google Patents

Abstract

PURPOSE: To readily achieve a desired degree of surface contact between two surfaces and a desired width of adhesive coating. CONSTITUTION: A layer of an adhesive having a controlled thickness and width is applied to the surface of a workpiece. A nozzle (14) having a flexible blade member with a concave adhesive-receiving surface 48 in combination with a rotary transfer roll (12) having a convex portion (20A) and side wall elements (18) forms a reservoir for adhesive on upstream (in the direction of roll rotation) of the contact line of an applying edge (52) of above surface (48) with the surface of the convex portion of the transfer roll (12). The apparatus is configured such that a layer of the adhesive, doctored by blade member (16) to control its thickness and its width controlled by the wall elements (18), is applied to the roll surface and carried to the operating locality.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an adhesive applicator, and more particularly, to an adhesive applicator for applying a layer of a molten moisture-curing adhesive to a surface portion of a workpiece placed at an operating position of the apparatus. Involved.

0002

BACKGROUND OF THE INVENTION A device of this type is disclosed in the applicant's co-pending Japanese patent application No. 01-159383 (Unexamined Japanese Patent Publication No. 2-
No. 191,568), the device comprises a cylindrical transfer roll disposed in an operative position with a transfer roll heater, and a straight cutting edge held in line contact engagement with the surface of the transfer roll. and a flexible vane member, the upstream face (in terms of the direction of rotation of the transfer roll) of said member being inclined at an acute angle to a horizontal plane passing through a line of contact with the surface of the transfer roll and with the vane member. and two further wall elements are disposed on opposite sides of the vane member and extend upstream therefrom in sealing engagement with the transfer roll, thus connecting the vane member with the surface of the transfer roll. forms a reservoir in which the molten adhesive is delivered from its supply device, and the device is such that a transfer roll rotates a layer of molten adhesive, the thickness of which is flexible Determined by the vane member, the layer is formed on a transfer roll and transported to the operating position.

[0003] The adhesive is then supplied by a cylindrical transfer roll, depending on the hardness of the material of which the roll is made, in which case the surface to be applied, for example the peripheral part of a shoe sole, is to some extent convex. up to slightly beyond the edge of the sole if the roll is relatively soft, up to the edge if the roll is of medium hardness (otherwise slightly deformed), or beyond the edge if the roll is relatively hard. In turn, the actual width of adhesive applied is determined by the pressure applied by the operator applying the surface to the roll.

0004

However, in practice it has been found that in most cases a roll of appropriate hardness can be selected to suit the needs of the individual application; In a few situations, individual needs cannot be met using cylindrical rolls. For example, in the case of a shoe sole where the outsole is secured with adhesive, if the outer edge of the outsole is well inside the outline of the sole, the adhesive must be applied to avoid any visible adhesive marks on the finished shoe. It is important that the edges of the membrane are coated excluding the edges of its surface. Even with hard rolls, this is difficult to achieve, especially when the surface is relatively flat and the edges are sharply formed. Moreover, it has also been found in practice that it is necessary to space the edge of the adhesive coating further from the edge of the sole in the medial waist area than in the front area. If reliability is essentially dependent on roll hardness, it is not suitable for various applications of adhesives.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved adhesive applicator which operates in such a way that the problems mentioned above are substantially avoided. The present invention provides an adhesive applicator for applying a layer of moisture-curing adhesive in a molten state to a surface portion of a workpiece placed at an operating position of the device, wherein the adhesive applicator has a tapered tip and a coating blade. an applicator block comprising a flexible vane member forming an applicator block, the vane member being concave with respect to an axis extending transversely to the applicator blade; and a transfer roll disposed in an operative position with a heating device for heating the transfer roll and a drive device for rotating the transfer roll, the transfer roll having a surface on which the application blade of the vane member forms line contact engagement. the transfer roll having a convex surface portion, the transfer roll comprising:
The concave surface of the block is configured to be the upstream surface (in terms of the direction of rotation of the transfer roll), and further the adhesive applicator is arranged one on each side of the vane member, and the adhesive applicator is arranged one on each side of the vane member, two side walls sealingly engaging the surface of the roll on opposite sides of the convex portion, whereby the vane member and the surface form a reservoir in which molten adhesive is delivered and received from the supply device; and the two sidewall elements cause the transfer roll to rotate a layer of molten adhesive, the thickness of said layer being determined by a flexible vane member, and said layer being formed on the surface of the transfer roll. , is fed into the operating position and is characterized in that the transfer roll is made of a material that is deformable under pressure, giving the operator adequate control over the amount of deformation.

Regarding operator control, by clarifying the degree of deformation of the material on the convex surface of the transfer roll, the material should not be easily deformed under weak pressure so that the operator can easily control the deformation. is understood, but at the same time there would be no need for excessive force applied by the operator to again result in reduced control. Rather, the material deforms over a range of pressures that are within the capability and immediate control of the operator throughout the working day. Shore hardness A of approximately 50°
has been shown to be suitable for this purpose.

In order to achieve surface contact between the surface of the transfer roll and the surface of the workpiece using the device of the invention, it is necessary to deform the convex portion of the transfer roll, since only line contact is effective between them. is necessary. By being able to easily control the amount of deformation, the operator can also control the width of the applied adhesive film and can actually vary the width depending on the needs of the application. .

It is naturally desirable that the thickness of the adhesive layer can be set in advance depending on the type of coating material, etc., and for this purpose preferably a blade member control device is provided, whereby: The force holding the flexible vane member in engagement with the transfer roll changes, thereby changing the thickness of the layer of melted adhesive formed on the surface of the transfer roll. Therefore,
Conveniently, the control device for the vane member comprises a pressure member which engages the downstream face (in terms of the direction of rotation of the transfer roll) of the linear tip of the vane and which is directed towards the transfer roll. You can move towards or away from it.

[0009] The molten adhesive is conveyed to the reservoir in any suitable manner, but in the case of the device described in the above-mentioned Japanese patent application, preferably the flexible vane member is combined with the adhesive supply device. It is defined by an internal passageway connected to an opening leading to said upstream surface of the vane member. In this method, the vane member itself forms part of the adhesive supply system, and in particular forms the last part of the system. This is of course advantageous if the device is left for a long period of time and the exposed adhesive, i.e. the adhesive at the closest point of the supply path, is exposed to the atmosphere and hardens. Due to the flexibility of the vane member from which the final portion is formed, the cured adhesive is easily removed. Moreover, such removal is even easier if the flexible vane member is made of silicone rubber.

[0010] The convex part of the transfer roll of the device according to the invention is suitably arranged with an outer surface of a material which is harder than the deformable material of said part and to which the adhesive has a lower adhesion. Preferably, the material forming the outer surface is polyethylene and the deformable material is silicone rubber. By providing the outer surface as described,
It has been found that it is possible to peel the cured adhesive away from the buildup of the cured adhesive once it has formed on the surface.

[0011] The side wall elements defining the outer edges of the layer of adhesive transferred to the transfer roll are preferably mounted on both sides of the convex part of the roller on carriers which are elastically engaged with the transfer roll. Advantageously, the pressure member is also mounted on said carrier for movement towards or away from the transfer roll as described above. Furthermore, to facilitate access to the flexible vane member, it is advantageous to
The carrier is mounted for movement between operative positions and has sidewall elements disposed on each side and at the corners of the flexible vane member.

Although any type of suitable equipment can be fitted to heat the transfer roll, one convenient form of heating equipment is to connect it to a source of hot air and to direct the hot air onto the surface of the transfer roll. It consists of a conduit directed to. Furthermore, for convenient construction, the conduit may be fixed to a carrier or the carrier may be attached to the conduit, and the conduit itself may be attached to a cradle part of the device for pivoting movement.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The apparatus described herein is generally similar to the above-mentioned Japanese patent application, except as noted below. The device described above is suitable for applying a layer of molten moisture-curing adhesive to a surface portion of a workpiece placed in the operating position of the device, and specifically, although not exclusively, A layer of this type of adhesive is suitable for applying to the periphery of the sole in accordance with the last for attaching the outsole. In this way, the apparatus forms an operational position in which the transfer roll 12 is located and a flexible vane member 16 in which adhesive is applied to the surface of the transfer roll 12 in a layer of controlled thickness. It consists of an applicator block or nozzle 14. Additionally, on either side of the vane member 16 there are two side wall elements 18 which are operative to control the width of the layer of adhesive applied to the transfer roll 12. The vane member 16 and the sidewall element 18 are arranged with respect to the transfer roll 12 so as to form an adhesive pool in which molten adhesive is supplied and received, as described below;
As the roll 12 rotates, a layer of molten adhesive, straightened by the vane member, is arranged to be directed onto the surface of the roll into an operative position.

The transfer roll 12 has a central convex portion 20A,
It consists of a core 20 of deformable material shaped to form side wall elements 18 and two cooperating outer parts 20B. Furthermore, covering the core is an outer adhesive-receiving layer or skin 22 which is hard compared to the hardness of the core and has low adhesive strength to the adhesive. A suitable material for the core has been found to be silicone rubber with a shore hardness of about 50° A. Materials suitable for the outer skin 22 are:
It turned out to be polyethylene, in fact a polyethylene tube that had been shrunk around the core 20. This type of polyethylene is manufactured in the UK under the trade name Elashlink.
It can be purchased from Hellerman Electric Co., Plymouth, Devon.

The transfer roll 12 has a core 20 connected to a hollow shaft 24.
is assembled by attaching washers 26 to it, one on each side, and then shrinking the skin over the core and washers. Furthermore, in order to attach the transfer roll 12 to the apparatus, a shaft 28 is rotatably mounted on a cradle 30 of the apparatus between a horizontal operating position and a mounting position in one corner, and in the latter position mentioned above. , the hollow shaft 24 of the roll 12 can be slid onto the shaft 28. In the operating position, opposite the shaft 28 is a drive shaft 32 which supports a manually retractable sleeve 34, which is spring biased towards the shaft 28. The drive shaft 34 has an oblique plate-shaped projection at its end,
When the projections are at the ends of the hollow shafts 24, they fit into corresponding holes to form a driving engagement with the shafts 24 and 32, thereby driving the rolls 12. sleeve 34
When the sleeve is retracted, the shaft 28 reaches its operative position, and when the sleeve is released, it holds the transfer roll in driving engagement with the drive shaft 32 in the operative position. The drive shaft 32 is driven by a belt-pulley arrangement comprising a belt 36 and driven by a motor (not shown).

The transfer roll 12 is driven in such a way that the above-mentioned surface portion thereof, ie the surface portion closest to the operator, moves in a downward direction, so that when placing a shoe sole on the roll, the operator can move the shoe himself. It can be moved in an almost straight line away from the When heating the roll, a heating device is installed in the form of a tube 42 through which hot air is directed towards the surface of the roll, in order to keep the adhesive delivered in a molten state. The temperature of the air must be high enough to maintain the melted adhesive but not cause damage to the transfer roll skin 22. It was found that a temperature range of 85-145°C gave suitable results, with the optimum temperature being about 120°C.

In conjunction with the transfer roll 12, the nozzle 1
4 is placed above the roll (see Figure 2), and 70
having two surfaces 48 and 50 inclined to each other at an apex angle of °;
It also consists of a main body 46 made of silicone rubber that forms a coating blade 52 between these surfaces, and the coating blade is held against the surface of the convex portion of the transfer roll (as will be explained later).

The upstream face 48 of the nozzle (in terms of how roll 12 rotates) is concave with respect to an axis transverse to applicator blade 52 . More specifically, an abstract line extending on the surface of surface 48 and parallel to said axis extends tangentially to the surface of transfer roll 12 at the point of contact between said surface and said abstract line. It forms an acute angle to the plane. In addition, the applicator blade 52 is offset from the top dead center of the transfer roll 12 by an angle of about 34° with respect to the axis of rotation of the roll.

In the operating state of the device, the adhesive is directed between the concave surface 48 of the body 46 and the surface of the transfer roll 12, forming a pool, ie a reservoir upstream of the applicator blade, which A layer of adhesive of controlled thickness acts as a straightening vane that is fed to the surface of the roll. In order to deliver the adhesive to the reservoir, the body 46 is formed with an internal passageway 54 that opens into the concave surface 48 via a slot 56 through which the adhesive is delivered.

The hot air conduit 42 supports supports 82 of the two sidewall elements 18, which support the transfer rolls 12.
It is formed of an arch-shaped engagement surface that sealsly engages with the surface portion 20B of. The hot air conduit 42 and thus the support 82 pivot about a horizontal axis to move the side wall element 18 to a corner position when access to the nozzle body 46 is desired. Additionally, it is desirable that the sidewall elements 18 are spring biased into engagement with the transfer roll surface. The support platform is thus pushed downwards by engagement with the two spring plungers 84 supported by the housing of the nozzle 14, and the support platform is pushed downward by the side wall elements between the portion 20B of the transfer roll and the side wall element. It is maintained in the operating position by engagement. The support stand 82 also supports a slide 8 which is sequentially supported by a pressure member 90 that constitutes a blade control device of the device.
Holds 8. The pressure member is located on the downstream surface 50 of the body 46 adjacent to but slightly spaced apart from the applicator blade.
, and the coating blade is transferred to the portion 20 of the roll surface.
It is in line contact engagement with A. The force applied to the transfer roll surface by the applicator blade varies depending on the position of the pressure member 90, which is adjusted by moving the slide 88 in the longitudinal direction of the support base 82. To this end, the rotation knob 92 is connected to the slide and held by a threaded engagement with the support so that rotating the rod causes the slide to move longitudinally of the support and direct the pressure member towards the nozzle. body 46 in a desired relationship.

The upstream face 48 of the body 46 whose tip forms the applicator blade thus forms, together with the side wall element 18 and the surface of the transfer roll 12, a receptacle or reservoir for the adhesive fed through the slot 56. This causes, as the transfer roll 12 rotates, a band or layer of adhesive to be applied to the surface of the roll, the thickness of said layer being determined by the straight blade.
It will be appreciated that in practice it is controlled by the force applied thereto and the width of the layer is controlled by the sidewall elements 18. It has also been shown that the hardness of the nozzle also influences the thickness of the applied layer and that the suitable hardness of the nozzle is in the range of 50-60 measured on the International Rubber Hardness Scale for normal applications. Of course, this will also be acknowledged.

When the operator applies adhesive, the speed at which the operator moves the surface of the workpiece, eg, the sole of a shoe, must be approximately the same as the circumferential speed of the transfer roll 12. A worker operating normally is expected to move the sole at a speed equal to the roll speed of approximately 90 rpm (applying a consistent layer of adhesive to the surface of the transfer roll will require a significantly faster roll speed). ). Therefore, the rotational speed of the rolls is preferably in the range of 75 to 100 rpm. A speed of 80 rpm is acceptable in most cases.

When using the device according to the invention described above,
The surface of the transfer roll 12 is maintained at a suitable operating temperature by blowing hot air from a conduit 42 onto the roll;
Thus, the layer of adhesive on the roll remains in an uncured state ready for application, if only for a limited time. A puddle of adhesive is contained within the reservoir formed by the surface of the roll, the concave surface 48 of the flexible vane member 16, and the sidewall element 18, and the adhesive continues to slowly harden. Will. When an operator wants to apply adhesive to the surface of a workpiece, such as a shoe sole, he operates a pedal (not shown) so that the adhesive flows through the internal passage 5 of the nozzle body 46.
4 to the said pool, and at the same time the operator:
By pressing the workpiece surface against the convex part of the transfer roll surface and moving the workpiece surface in response to the roll,
Apply a layer of glue. At or shortly before the end of application, the operator releases the pedal and valve 80 returns to the closed position. The convexity of the surface and the variability of the core 20 allow the operator to achieve the desired degree of surface contact by applying a desired but easily controllable pressure to press the workpiece surface against the surface. is performed between the transfer roll and the workpiece surface to sufficiently deform the core so that a coat of applied adhesive of the desired width adheres to the workpiece surface.

[Brief explanation of the drawing]

1: Applicator block of the device according to the invention,
It is a sectional view showing details of a transfer rake and a side wall.

FIG. 2 is a front elevation detail view showing the installation of the transfer roll.

Claims (14)

[Claims] 1. An adhesive applicator for applying a layer of moisture-curing adhesive in a molten state to a surface portion of a workpiece disposed in an operating position of the apparatus, wherein the adhesive applicator has a tapered tip and a coating surface. an applicator block comprising a flexible vane member forming a blade, the vane member being concave with respect to an axis extending transversely to the applicator blade; a transfer roll disposed in an operative position with a block and a heating device for heating the transfer roll and a drive device for rotating the transfer roll, the transfer roll having a surface on which the application blade of the vane member forms line contact engagement; the transfer roll having a convex portion with (), the transfer roll having a concave surface of the block (
the upstream side (in terminology of the direction of rotation of the transfer roll), further comprising: one adhesive applicator disposed on each side of the vane member; having two side wall elements in sealing engagement with the surfaces of the vane member and said surfaces thereby forming a reservoir in which molten adhesive is delivered and received from the supply device; The element causes the transfer roll to rotate a layer of molten adhesive, the thickness of said layer is determined by a flexible vane member, said layer is formed on the surface of the transfer roll, and is conveyed to an operating position and the transfer roll An adhesive application device characterized in that the adhesive applicator is made of a material that is deformable under pressure giving the operator adequate control over the amount of deformation. 2. A vane member control means is further provided for varying the force with which the flexible vane member is engaged with and held by the transfer roll, thereby controlling the molten adhesive formed on the surface of the transfer roll. 2. A device according to claim 1, characterized in that the thickness of the layers is varied. 3. The vane member means (in terms of the direction of rotation of the transfer roll) of the vane member adjacent to the applicator blade.
3. The device of claim 2, further comprising a pressure member engageable with the downstream surface and movable towards or away from the transfer roll. 4. For conveying adhesive to a reservoir, the flexible vane member is formed with an internal passageway connected to an adhesive supply device and an opening in the upstream face of the vane member. The apparatus according to any one of claims 1 to 3, characterized in that: 5. Claims 1 to 4, wherein the flexible blade member is made of silicone rubber.
The device described in any of the above. 6. The convex portion of the transfer roll has an outer surface of a material that is harder and exhibits a lower adhesive strength than the deformable material of the convex portion. The apparatus according to any one of claims 1 to 5. 7. The device of claim 6, wherein the material forming the outer surface is polyethylene. 8. Apparatus according to claim 1, characterized in that the deformable material from which the convex portion of the transfer roll is made has a Shore A degree of approximately 50°. 9. Device according to claim 1, characterized in that the deformable material from which the convex portion of the transfer roll is made is silicone rubber. 10. Claims 1 to 10, characterized in that the side wall elements are attached on opposite sides of the convex portion of the transfer roll to supports which are resiliently engaged with the transfer roll. 9. The device according to any one of 9. 11. The apparatus of claim 10, wherein the pressure member is mounted on a support for movement toward or away from the transfer roll. 12. Claim 10, characterized in that the support is mounted for movement between an operating position and a corner position, in which the side wall elements are located on either side of the flexible vane member. or the apparatus according to claim 11. 13. The heating means for the transfer roll comprises a conduit connected to a source of hot air and directing the hot air onto the surface of the transfer roll. equipment. 14. Apparatus according to claim 13, characterized in that the conduit is fixed to a support.