JPS5955703A - Method of joining veneer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field The present invention relates to a veneer veneer (hereinafter referred to as a veneer) using a bonding thread coated with or impregnated with a thermoplastic adhesive.

This invention relates to a veneer joining method in which the veneers are joined together by intermittent pressure bonding at the joint portions of the veneers.

Prior Art Conventionally, in the veneer joining method of joining narrow veneers to each other to form a one-piece veneer, for example,
As described in Japanese Patent No. 4-3928, a thermoplastic adhesive (hereinafter referred to as adhesive) is used.

) is coated or impregnated with a fixed amount of heated air heated to a high temperature by an electric heater to melt the adhesive of the bonding yarn into a highly viscous state. A commonly known method is to join veneers together by crimping the joints of the veneers, cutting the joining threads to a length corresponding to the joining of the joints, and intermittently gluing the joining threads to the joints. However, if the waiting time for the bonding thread to be crimped to the joint is long, the adhesive will over-melt and become less viscous, causing some of it to drip down and reduce the adhesion in the bonding thread that is crimped to the joint. Since the amount of agent is small, the veneers cannot be bonded together with sufficient bonding strength.

In addition, in order to solve the above-mentioned drawback, that is, low viscosity due to overmelting of the adhesive, after Fm melting the adhesive at a high viscosity, the air supplied to the electric heater is cut off or the amount of air is reduced. In the method of maintaining the molten state of the adhesive at a high viscosity, the electric heater heats up to several hundred degrees, so the electric heater easily breaks, which increases the frequency of replacement and reduces work efficiency. It had

Purpose of the Invention In view of the above-mentioned conventional drawbacks, the purpose of the present invention is to provide a method for joining veneers that can obtain high joint strength by melting an adhesive with high viscosity while preventing heater disconnection by a simple means. The purpose is to provide a method.

Composition of the invention The method of the present invention will be explained below according to Examples.

FIG. 1 is an explanatory diagram showing an outline of a veneer joining device embodying the veneer joining method according to the present invention, FIG. 2 is an explanatory diagram showing an outline of a joining thread feeding device and an adhesive melting device, FIG. 3 is a plan view of FIG. 2, and in the figure, a large number of veneers 4 are carried at appropriate intervals in a direction perpendicular to the conveyance direction of the veneers 4 carried onto the anvil roll 3 by the carrying-in device 2. A thick/thin detector 6 detects the cutting position at the front edge and rear edge of the veneer 4 in accordance with the elevation of a detection roll 5 which is arranged and comes into contact with two surfaces of the veneer 4; 6 changes from the veneer non-detection state to the veneer detection state, the uneven portions at the curved edges of the veneer 4 are detected, and at least one of the thickness and thinness detectors 6 changes from the veneer detection state to the veneer non-detection state. When the state changes to the detection state, the cutting blade 7 that cuts the uneven part on the rear edge of the veneer 4 is driven to open and close in conjunction with the cutting operation of the cutting blade 7, and the uneven part is cut by Jk.
It consists of a sorting opening/closing body 8 that carries out the cut effective veneers to a subsequent process. In the figure, reference numeral 9 is a feed roll disposed on the delivery side of the cutting blade 7 to carry out the veneer 4 to the subsequent process, and 10 is a cutter for scraping off irregularities on the front edge of the veneer 4 to the outside of the conveyance path. At appropriate intervals in the direction perpendicular to the conveying direction of the veneer 4 3
- a large number of actuating devices such as eccentric rods, cams, or hydraulic cylinders [not shown]; ] Auxiliary pressure body 1 pivotably mounted on a shaft 12 that is reversibly rotated at a predetermined angle.
3 is rotatably supported on the proximal end side of the auxiliary pressurizing body 13, and as the shaft 12 is driven in the forward direction, the tip FM of the auxiliary pressurizing body 13 cooperates with the large diameter portion 12a of the shaft 12. 1t
The joining thread 15 protrudes from the through hole 14 formed in the
The crimping surface 21 of the crimping device 16 (described later)
8. Let out the thread 15 by the length necessary for joining the veneers 4 with respect to III, pull back the joining thread 15 according to the reverse drive of the shaft 12, and stick the tip 15a out of the through hole 14 by the length necessary for joining. It consists of a feeding roll 17. still,
In the figure, 18 is a splicing yarn guide tube through which the splicing yarn 15 passes from the feed roll 17 to the through hole 14.

A thermoplastic adhesive (hereinafter referred to as adhesive) that melts at about 100 to 150° C. is coated or impregnated onto a single yarn such as nylon 711m fiber, Tetron fiber, cotton, or cotton fiber. 4- Yes.

The adhesive melting device 19 is attached to the distal end side of the auxiliary rotation pressure body 13, and is supplied from an external compressor to the distal end portion 15a of the bonding thread 15 protruding from the through hole 14, and is connected to a built-in electric heater (not shown). ) about 150-20
A fixed amount of heated air A heated at a high temperature is blown onto the adhesive to melt the adhesive into a bondable state.

The rectifying device 20 intermittently blows air B supplied by an external compressor onto the heated air A from an injection nozzle 20a attached to a pressurizing part 13a formed at the tip of the auxiliary pressurizing body 13, thereby heating the air. The air A is rectified and regulated in a direction other than the tip end 15a of the joining thread 15 to prevent the heated air A from overmelting the adhesive.

A large number of crimping devices 16 are arranged at intervals corresponding to the feeding devices 11 on the input side of the cutting blade 7, and are used to separate the rear wheel portion of the preceding veneer 4 that has been cut to some extent on the anvil roll 3 and the following veneer 4. The crimping surface 21a is brought into pressure contact with the joint part 4a where the front wheel part of the plate 4 is close to or in contact with,
A pressure bonding member 21 that adheres the joining thread 15 fed out by the feeding device 11 and a pressure bonding surface 21 a fl! on the loading side of the pressure bonding member 21 where heat is exchanged by passage of a cooling liquid. A cooling member 22 that cools the ll
and a bonding thread 15 that is attached between the crimping member 21 and the cooling member 22, has a cutting edge protruding from the crimping surface 21a in a manner corresponding to the thickness of the bonding thread 15, and is bonded to the bonding portion 4a. and a thread cutting knife 23 for cutting the thread. still,
The crimp member 21 is configured to be movable up and down by a shaft (none of which is shown) that is reversibly rotated at a predetermined angle by an operating member such as an eccentric rod, a cam, or a hydraulic cylinder. Alternatively, a cooling liquid may be passed through the pressure bonding member 21 to directly cool the pressure bonding member 21 itself.

Next, a method for joining veneers using the apparatus of this embodiment will be explained with reference to FIGS. 4 to 6.

The adhesive melting device 19 connects the bonding thread 1 protruding from the through hole 14.
After blowing heated air A onto the tip 15a of the tip 15a to melt the adhesive at the tip 15a to a high viscosity that can be bonded, the rectifier 20 is set in advance according to the melted state of the adhesive. Air B is blown against the 0M heated air A every hour, and the blowing direction of the heated air A is rectified in a direction other than the tip 15a to prevent the adhesive from becoming low in viscosity due to overmelting. Holds the adhesive in a molten state of high viscosity that allows it to bond.

On the other hand, the veneers 4 from which uneven parts at the front and rear edges of the veneers 4 have been cut and removed by the sizing cutting device 1 are placed on the anvil roll 3 with the rear and front ends close to each other or in contact with each other. be located. Then, by driving the shaft 12 in normal rotation, the splicing yarn 1
The tip 15a where the adhesive in No. 5 is melted is connected to the joint portion 4.
After feeding out between the crimping surface 21a and the crimping surface 21a, the tip 15a is cooled as the crimping member 21 moves downward while joining tJ4a.
The thread cutting knife 2 is pressed to harden the adhesive.
3, the joining thread 15 is attached at a length corresponding to the joining of the joining part 4a.
cut. Incidentally, when the splicing yarn 15 is fed out, the rectifying device 20 blows out the air B to restrict the melting of the splicing yarn 15 by the heated air A. Further, when cutting the joining thread 15, the joining thread 15 is pulled back by the reverse rotation of the shaft 12, so that the joining thread 15 can be reliably cut.

By repeating the above operation, the bonding threads 15 are intermittently bonded to the bonding portions 4a, thereby bonding the veneers 4 to each other. It is also possible to cut the joined veneer 4 into predetermined lengths by driving the cutting blade 7 to form a one-piece joined veneer.

Therefore, in the method of this embodiment, the tip portion 15a is always kept at a constant air volume.
Compared to the conventional method of melting an adhesive, this method prevents the bonding strength from decreasing due to dripping of the adhesive whose viscosity has been reduced by overmelting.

Furthermore, compared to the conventional method of blocking or reducing the amount of air blown to the tip M portion 15a of the joining thread 15 and preventing the adhesive from becoming low in viscosity due to overmelting, it is possible to reduce the disconnection rate of the electric heater. Yes, it is possible to simplify maintenance management.

In addition, as a means for rectifying the injection direction of the heated air to the tip of the bonding thread protruding from the through hole, = 8 - For example, a rectifying plate is installed near the injection port in an adhesive melting device i, and a rectifying plate is installed at a predetermined time interval. A configuration in which a current plate is moved to rectify the jetting direction of the heated air to a direction other than the tip of the joining yarn, or an adhesive melting device is installed so that the jetting direction of the heated air can be varied, and the adhesive at the tip of the joining yarn is After melting the adhesive, heated air is injected in a direction other than the tip to prevent excessive melting of the adhesive.

As described in detail, the present invention involves blowing heated air onto the tip of a joining thread coated with or impregnated with a thermoplastic adhesive to melt the thermoplastic adhesive of the joining thread; The bonding thread is crimped to the joint of the veneer veneer, the joining thread is cut to a length corresponding to the joining of the joint, and the joining thread is intermittently glued to the joint, thereby forming the veneer veneer. In the joining method of joining each other, after the thermoplastic adhesive is melted by heated air, the blowing direction of the heated air is rectified in a direction other than the tip of the joining thread, and the viscosity of the thermoplastic adhesive is reduced by overmelting. This is a veneer joining method that uses a simple means to regulate the temperature and melts the adhesive at high viscosity while preventing heater disconnection, thereby achieving high joining strength.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing an outline of a veneer joining device embodying the veneer joining method according to the present invention, FIG. 2 is an explanatory diagram showing an outline of a joining thread feeding device and an adhesive melting device, FIG. 3 is a plan view of FIG. 2, and FIGS. 4 to 6 are explanatory diagrams showing the joined state. In the figure, 4 is a veneer, 4a is a joint, 15 is a joining thread, and 15a is a tip. , A is heated air. Patent applicant Meinan Seisakusho Co., Ltd. Agent Patent attorney Ken Ito −

Claims (1)

[Claims] 1. After blowing heated air onto the tip of the joining thread coated or impregnated with a thermoplastic adhesive to melt the thermoplastic adhesive of the joining thread, the joining thread is used to join the veneer veneer. In a joining method in which veneer veneers are joined together by crimping the parts, cutting the joining thread to a length corresponding to the joining of the joining parts, and intermittently adhering the joining thread to the joining parts, heating is used. A veneer characterized in that after the thermoplastic adhesive is melted by air, the blowing direction of the heated air is rectified in a direction other than the tip of the bonding thread to prevent the thermoplastic adhesive from becoming low in viscosity due to overmelting. How to join veneers.