FI64907C - ANSLAGSANORDNING FOER ANVAENDNING VID HANTERING AV SAOGAT VIRKE - Google Patents

Description

64907

Sawn timber handling equipment Anslagsanordning för användning vid hantering av sägat virke

The invention relates to a counter-device for controlling the movement of sawn timber pieces used in connection with a cross-conveyor and a longitudinal conveyor of sawn timber, which is used to stop the longitudinal movement of sawn timber

In the previously known devices on which the invention is based, the kola-10 conveyor moves the pieces of lumber transversely, while against this conveyor a transverse roller conveyor moves the pieces in the longitudinal direction. When the longitudinal displacement has reached a predetermined distance, e.g. In order to prevent the sawn timber pieces from continuing to move longitudinally by sliding on the lifting members, which they tend to do under the influence of continuity, and because the friction between the lifting members and the timber cannot prevent this, the device is fitted with 20 oblique stops pressed by the timber piece head.

One of the structures described above is disclosed in FI patent application No. 751931, which discloses a timber base cutting station in which a conveyor belt is used in response to that described above. However, this known direct response cannot prevent the longitudinal movement of the piece of timber from continuing even after the transfer effect of the transport rollers has ceased, but the stopping remains to be performed by the lifting members. However, the limited friction between these members and the sawn timber causes the sawn timber not to stop immediately and accurately in its longitudinal lifting position, but to continue the indefinite distance forward. This means inaccurate felling of timber.

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The object of the present invention is to eliminate the above-mentioned drawback and to provide a longitudinal displacement response which forms an end barrier to the advancement of the sawn timber piece while the lifting device lifts the goods off the roller conveyor. The invention is mainly characterized in that the abutment device has a curved part in the main conveying plane, the shape of which is such that when the main conveying direction of the sawn timber is denoted by x and the longitudinal conveying direction by y, the curved part of the stop is substantially k * x such that the end of the sawn timber pieces remains in contact with said curved part at all the transverse conveyor speeds present and the normally occurring coefficients of friction between the longitudinal conveyor and the sawn timber pieces.

The curved part of the abutment device according to the invention can also be formed obliquely in the lifting direction of the timber pieces against the longitudinal direction of movement of the timber pieces so that during the lifting movement and the simultaneous transverse transport movement of the timber pieces the head

As shown, a sawn timber length transfer device is provided, the response of which stops the movement of the sawn timber piece efficiently and accurately. In this way, higher transport speeds can be used and 25 fewer wastes are obtained than with previously known devices.

The invention will now be described in detail with reference to an application example of the invention shown in the figures of the accompanying drawing, to the details of which the invention is in no way limited.

Figure 1 shows an overview of a timber handling device using a skewed response according to the invention.

Figure 2 shows the structure in more detail in section 11-11 of Figure 1.

Figure 3 shows the ideal longitudinal shape of the response.

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The pieces of timber 1 are conveyed by means of the coulter conveyor cavities 2 transversely at a constant speed towards the base cutting blade 3. When the pieces 1 come to the roller conveyor rollers 4 and are supported by them, the rollers 4 start moving them to the right 5 towards the straight part 5 of the stop. , the hoists 6 driven by the working cylinder 8 via the arm 9 lift the body 1 off the support of the rollers 4 before it has a response to the curved part 7. In this way, the piece 1 is further moved by the pins 2 and just past the cutting blade 3.

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If the end of the part deviates from the cutting line, such as with the part la, the distance Δ, the rollers 3 move the part of the part against the straight part 4a. The purpose is to get the end of all pieces of sawn timber on the same line before moving for base cutting.

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If a certain part of the base end is predetermined to be removed from the body 1, the rollers 4 continue the longitudinal movement of the bodies 1 within the limits allowed by the curved part 7 of the stop. The part to be removed can be marked at the inspection site, as described in more detail in FI patent application No. 751931, with a fluorescent paint.

In this case, as the timber passes longitudinally on the rollers 4 past the main conveying photocell device in the linear direction, this device gives an impulse at the fluorescent mark and the lifting device 6,8,9 lifts the piece 1 off the conveyor rollers 4, stopping its longitudinal movement and the piece 1 transported to the breaker blade 3, which cuts it at the marked point.

In order for the sawn timber longitudinal stopping device to function as intended in the invention, the longitudinal shape of the stop 7 is arranged so that the ends of the sawn timber to be moved remain in contact with the stop 7 at all times. When the sawn timber piece 1 is at the straight part 5 of the stop, its longitudinal velocity is v ^ = 0.

Since the coefficient of friction between the rollers 4 and the pieces 1 may vary, the different pieces 1 tend to accelerate in their longitudinal movement 35 at different intensities. In order for all the pieces 1 to be supported to reach the curved response part 7 at all times, the part 7 is shaped to correspond to the values of the lowest coefficient of friction and the highest coulter speed used.

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The curvature of the part 7 becomes gentler, the lower the friction through which the sawn timber moves in the longitudinal direction and the faster it travels in the transverse direction.

5 According to Figure 1, the longitudinal displacement of the sawn timber is denoted by y and the transverse displacement by x. As the body 1 moves at a constant transverse velocity νχ there is a displacement x = νχ t.

If the part moves simultaneously at an accelerating speed in the longitudinal direction 2 2 y, a displacement y = 1 / 2a 't = 1 / 2μ · g t is obtained, where 10 a = acceleration μ = coefficient of friction between the sawn timber piece 1 and the rollers 4 g = acceleration of the ground force.

2 - ·· X Li · £ * X, U * £ 15 Placing t = - gives y = —-®- = k · x, where k = -.

v o 2 o 2 x 2 · v ^ 2v x x

By placing in this formula the highest value present for the transverse transfer rate νχ and the lowest value in question for the coefficient of friction, the formula gives the shape of the curved part 7 20 of the response which satisfies the objects of the invention. For example, if 100 coke is driven per minute with a cavity spacing of 700 mm and the minimum coefficient of friction h is assumed. = 0.23, yields: mm k = ° - * · 2—- -9 ^ ~ = 0.83.

2 · 1,1672 25 The longitudinal shape of the lumber response is then described by the parabola y = 0.83 · x2.

The maximum deviation from the displacement required by a straight sloping surface is 30, 2 kx where Xq = the length of the stop in the transverse direction of the sawn timber piece.

35 For example, if xg = 600 mm, the deviation Ay = 75 mm is obtained.

64907

From the above calculation example, it is observed that when using a direct response, considerable errors can occur in the cutting of the sawn timber if the driving speed is so high that the end of the sawn timber comes off the response.

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The curved part 7 of the stopping response can advantageously be vertically inclined as shown in Fig. 2. Thus, the oblique stop 7 moves the end of the timber as the lifting device lifts it a short distance "backwards". When the coulter conveyor 1 transports the timber piece 1 at the same time forward, the timber piece 1 can be arranged to move in the vertical plane in the main conveying direction. In other words, in two cuts, the curved stop 7 terminates the longitudinal movement of the pieces of sawn timber 1 very precisely.

15 It is obvious that the vertical inclination of the part 7 of the stop depends on the speed of the cola conveyor and the lifting speed of the lifting device 6,8,9. The higher the lifting speed, the more gently vertically inclined stop part 7 is necessary.

As shown in Fig. 1, the curved abutment portion 7 is preceded by a straight abutment portion 5 parallel to the main conveying direction and in the same plane as the subsequent cutting blade 3. As an immediate and substantially tangential extension of the abutment straight portion 5, a parabolic curved portion 7 is mentioned. may be 25 straight response portions 10.

The following are claims within the scope of which the various details of the invention may vary and differ from those set forth above.

Claims (4)

1. A stop device (5,7) for controlling the movement of the timber pieces in connection with a cross conveyor (2) and a longitudinal conveyor (4) for sawn timber, which device is used for stopping timber movement longitudinally in a predetermined manner, for each piece freely selected position and in connection with which device the lifting means (6,8,9), which lifts off the pieces of wood (1) from the grip of the longitudinal conveyor (4), operates, characterized in that the abutment device (5,7) in the the main transport plane has a curved portion (7), the shape of which is substantially the form y = k * x in the main transport plane since the main transport direction of the wood is denoted by x and the longitudinal transport direction with y such that the wood pieces (1) end up in contact with said curved portion (7). at all available speeds p1 the transporter (2) and at normally occurring coefficients of friction (p) between the length conveyor (4) and the wood pieces (1). 15 2. The abutment device according to claim 1, characterized in that the curved portion (7) of the abutment is formed obliquely also in the vertical direction, so that the lifting of the wood piece by the lifting device (6,8,9) together with the displacement of the piece in the transverse direction causes the contact point between the end of the piece of wood (1) and the surface of the abutment (7) moves forward and upwards along a path perpendicular to the longitudinal direction of the wood or deviating from it with a small distance in the direction of the longitudinal offset. 3. A stop device according to claim 1 or 2, characterized in that the stop device at the beginning end of the longitudinal conveyor (4) has a straight portion (5) which lies in a plane determined by a subsequent cutting (3), and that the curved portion in question. (7) of the abutment constitutes an immediate, substantially tangential extension of said straight abutment portion (5). 4. A stop device according to claim 1,2 or 3, characterized in that, after the curved stop portion (7),