VERTICAL PANEL SAW WITH PANEL LOWERING DEVICE

Description

[0001] The present invention relates to a vertical panel saw with a panel lowering device according to the preamble of independent claim 1. Such a panel saw, according to the preamble of claim 1, is disclosed in EP 0004926 A2.

[0002] Vertical panel saws are known from the prior art. These typically comprise a frame, usually positioned nearly vertically, and a saw unit adjustable to the frame via a saw beam. Panels to be sawn, particularly those made of wood and / or plastic, are placed against the frame and supported at the bottom by support elements, often designed as rollers. Some vertical panel saws have one or more panel lowering devices for lifting and lowering panels to be sawn, or already sawn panel sections, onto the support elements. These panel lowering devices include, for example, clamping jaws that are lowered onto a panel from above and then clamp it securely at the top edge. The height of the clamping jaws is adjusted using a height adjustment mechanism and a drive unit.

[0003] To prevent damage from excessive force when lowering the plate clamped with the clamping jaws onto the support elements, or conversely, when lowering the clamping jaws onto the plate to be gripped, this lowering process must be monitored at various points using multiple sensors, especially if additional support elements can be optionally added at other frame heights. Furthermore, highly precise control of the height adjustment is essential.

[0004] In view of the disadvantages of previously known vertical panel saws, the invention aims to create a vertical panel saw with an improved panel lowering device that minimizes the risk of damage associated with panel handling and / or reduces the monitoring means necessary for minimizing the risk of panel handling.

[0005] This problem is solved by the vertical panel saw according to the invention, as defined in independent claim 1. Preferred embodiments are set forth in the dependent claims.

[0006] The essence of the invention is as follows: A vertical panel saw comprises a frame, a saw unit adjustable on the frame, and a panel lowering device. The panel lowering device comprises a height adjustment mechanism with an adjustment drive and a panel holding unit for holding a panel, which is height-adjustable on the height adjustment mechanism. The height adjustment mechanism comprises a height-adjustable adjustment carriage, and the panel holding unit comprises a lifting carriage. The panel holding unit is kinematically connected to the adjustment drive via a freewheel, the freewheel interrupting the kinematic connection between the panel holding unit and the adjustment drive when a panel held by the panel holding unit is placed on a support.

[0007] The freewheel prevents excessively large opposing forces from acting on the plate holder and the height adjustment mechanism with its drive unit when a plate, held by the plate holder, is placed on a support, as the forces generated by the drive unit are decoupled. This means that even if the drive unit continues to run, it exerts no force on the plate holder unit that would further press the plate against the support, thus counteracting the force exerted by the support. This prevents damage caused by cumulative forces. Precise control of the height adjustment, which would ensure that the plate held by the plate holder is placed on the support with virtually no force and would require suitable monitoring devices, is not fundamentally necessary for this purpose.

[0008] In principle, the freewheel can also lead to a kinematic decoupling of the plate holding unit and the adjustment drive, or an interruption of the kinematic connection between the plate holding unit and the adjustment drive, if the plate holding unit is lowered onto the plate from above to grip it and the lowering is not stopped in time. However, since the plate holding unit is usually not placed completely flush against the plate, this occurs less frequently.

[0009] In a preferred embodiment, the lifting carriage rests detachably on the adjusting carriage.

[0010] The removable mounting of the lifting carriage of the plate holder unit on the adjusting carriage of the height adjustment device allows for a simple freewheel mechanism. When the lifting carriage is in contact with the adjusting carriage, raising the adjusting carriage also raises the lifting carriage, thereby raising the other connected parts of the plate holder unit. However, if the plate holder unit encounters resistance while lowering with the lifting carriage mounted on the adjusting carriage—for example, when a plate held by the plate holder unit is placed on a support or when the plate holder unit is lowered onto the plate from above and stopped too late—the upward force can cause the lifting carriage to detach from the adjusting carriage. This results in the adjusting drive running freely, and the kinematic connection between the plate holder unit and the adjusting drive is interrupted.

[0011] Advantageously, the height adjustment device includes an adjusting spindle that is rotatable by means of the adjusting drive, and the adjusting carriage is arranged on the adjusting spindle and can be adjusted in height by rotating the adjusting spindle. Such an adjusting spindle is a simple means of effecting a lowering or raising movement of the adjusting carriage with an adjusting force generated by the adjusting drive.

[0012] Preferably, the height adjustment device comprises at least one linear guide on which the plate holding unit is linearly guided. This ensures that the plate holding unit is held in a stable, adjustable position; it is adjustable relative to the linear guide only in one direction and its opposite direction, for example, it is slidable.

[0013] Advantageously, the plate holding unit features a release sensor that detects when the lifting carriage detaches from the adjusting carriage. Such a release sensor makes it possible to react to the detachment of the lifting carriage from the adjusting carriage and, for example, to stop the adjusting drive or even (briefly) move it in the opposite direction until the adjusting carriage is once again in contact with the lifting carriage and the plate holding unit is again supported by the adjusting carriage via the lifting carriage.

[0014] Advantageously, the plate holding unit is a clamping unit with a fixed clamping jaw and a movable clamping jaw, between which a plate can be clamped. The movable clamping jaw can be adjusted relative to the fixed clamping jaw by means of a clamping jaw drive, preferably pneumatic, and preferably guided linearly. Gripping and securely holding a plate with the plate holding unit can thus be achieved in a simple manner.

[0015] In an advantageous embodiment, at least one supply line of the panel holding unit is guided from a stationary area of ​​the vertical panel saw to the panel holding unit via two deflection pulleys. One of the two deflection pulleys is movably arranged such that the higher the position of the panel holding unit, the greater the distance between the two deflection pulleys. Preferably, the movably arranged deflection pulley is pre-tensioned away from the other deflection pulley. Routing a supply line of the panel holding unit via the two movably arranged deflection pulleys allows for an arrangement of the at least one supply line that is as space-saving and well-defined as possible in all adjustment positions of the panel holding unit. The at least one supply line never simply hangs down loosely and undefined.

[0016] Advantageously, the plate lowering device includes traction elements, preferably a tension spring or at least one magnet, that pull the lifting carriage towards the adjusting carriage. Such traction elements serve to pull the lifting carriage towards the adjusting carriage if possible, i.e., if this is not prevented by the plate holding unit, with or without a plate, resting on a support. In this way, the kinematic connection between the plate holding unit and the adjusting drive is ensured as quickly and effectively as possible.

[0017] Preferably, the vertical panel saw comprises two or more panel lowering devices, which are preferably adjustable synchronously. With two or more panel lowering devices, a panel can be held more stably than with only one. Furthermore, heavier weights can be lifted.

[0018] Advantageously, the vertical panel saw includes a control unit for controlling the panel lowering device, or two or more panel lowering devices. Such a control unit enables the targeted control of multiple panel lowering devices, particularly by an operator, but also potentially automatically by a control program.

[0019] The vertical panel saw according to the invention will now be explained in more detail with reference to an embodiment shown in the drawings. The drawings show: Fig. 1 - a front view of an embodiment of a vertical panel saw according to the invention with a panel held by two panel lowering devices; Fig. 2 - the vertical panel saw of Fig. 1 with another plate held by three plate lowering devices; Fig. 3 - a perspective view from an oblique front view of a plate lowering device of the vertical panel saw of Fig. 1; Fig. 4 - a perspective view from an oblique front view of the plate lowering device of Fig. 3 without front panel; Fig. 5 - a front view of the plate lowering device of Fig. 3 ; Fig. 6 - a front view of the plate lowering device of Fig. 5 without front panel, but with lifting carriage detached from the adjusting carriage; Fig. 7 - an enlarged view of detail A of Fig. 5 ; Fig. 8 - an enlarged view of detail B of Fig. 6 ; Fig. 9 - a partially schematic side view of the plate lowering device of Fig. 5 , in which housing parts are omitted from the plate holding unit; Fig. 10 - a partially schematic side view of the plate lowering device of Fig. 5 , in which housing parts are omitted from the height adjustment device; Fig. 11 - an enlarged view of detail C of Fig. 9 ; Fig. 12 - a partially schematic side view of the plate lowering device accordingly Fig. 11 with plate held and support for the plate; Fig. 13 - a perspective view from a rear oblique angle of the plate lowering device of Fig. 3 without rear panel; and Fig. 14 - an enlarged view of detail D of Fig. 13 .

[0020] The following convention applies to the description below: If reference symbols are indicated in a figure for the purpose of graphical clarity, but are not mentioned in the immediately corresponding descriptive section, reference is made to their explanation in preceding or subsequent descriptive sections. Conversely, to avoid graphical clutter, reference symbols that are less relevant for immediate understanding are not included in all figures. Reference is made to the remaining figures in these cases. Positional and directional terms such as above, below, upwards, downwards refer to the typical arrangement of the vertical panel saw shown in the figures.

[0021] Fig. 1 Figure 1 shows an embodiment of a vertical panel saw according to the invention with a panel 9 to be sawn arranged and held thereon. The vertical panel saw has a frame 2 comprising several vertical supports 21, a lower crossbeam 22, an upper crossbeam 23, and a support grid 24 arranged thereon for supporting the back side of the panels to be sawn, as well as several feet 26. A plurality of support elements in the form of support rollers 25 project from the lower crossbeam 22 along its length, serving as vertical support for the panels to be sawn. Fig. 1 The plate 9 rests on eight such support rollers 25.

[0022] The vertical panel saw further comprises three identical panel lowering devices 1, 1' and 1", spaced apart from one another, with which panels to be sawn can be securely held, lifted and lowered. The panel lowering devices 1, 1', 1" each have a height-adjustable panel holding unit 11, 11', 11" that can grip a panel to be sawn from above, over the upper edge of the panel. Fig. 1 The plate holding unit 11 of the plate lowering device 1 rests in its upper end position, while the plate holding unit 11' of the plate lowering device 1' and the plate holding unit 11" of the plate lowering device 1" have gripped and are holding the plate 9 at its upper end. The plate holding units 11' and 11" are lowered slightly from their respective upper end positions.

[0023] For sawing the panels, the vertical panel saw has, in a known manner, a saw unit 3 which is arranged on a saw beam 31 in a height-adjustable manner, i.e., essentially vertically adjustable, and which can be pivoted between a vertical cutting position, in which a vertical cut can be made, and a horizontal cutting position, in which a horizontal cut can be made. The saw beam 31 is guided on the frame 2 in a longitudinal direction along the lower and upper crossbeams 22, 23, so that a horizontal cut can be made by longitudinally or horizontally displacing the saw beam 31 with the saw unit 3 arranged on it. A vertical cut can be made by adjusting the height of the saw unit 3 along the saw beam 31.

[0024] The in Fig. 1The illustrated vertical panel saw also includes, in a known manner, a dust extraction device 5 for extracting sawdust and sawdust and a control cabinet 6.

[0025] Finally, the vertical panel saw comprises a control device 4 for controlling, in particular, the saw unit 3, the panel lowering devices 1, 1', 1" and the extraction device 5. The control device 4 is arranged on a control beam 41, which is adjustable along the frame 2 in the longitudinal direction of the upper crossbeam 23, i.e., it is longitudinally and horizontally displaceable like the saw beam 31.

[0026] Fig. 2 shows the same vertical panel saw as Fig. 1However, plate 90 is now arranged on this plate instead of plate 9. Plate 90 is much longer and narrower than plate 9 and is held by the plate holding units 11, 11', 11" of all three plate lowering devices 1, 1', 1". In the position shown, it is lifted off the support rollers 25.

[0027] The Figures 3-5 The figures show, as representatives of the structurally identical plate lowering devices 1, 1', 1", plate lowering device 1 in a perspective view from a slightly oblique front view ( Fig. 3 ), in a perspective view from a slightly front angle without front fairing ( Fig. 4 ) and in a front view ( Fig. 5 ). In Fig. 7 is detail A of Fig. 5 shown enlarged.

[0028] The plate lowering device 1 comprises a height adjustment device 10 and a plate holding unit 11 arranged on the height adjustment device 10 in a height-adjustable, i.e. essentially vertically adjustable, manner for holding a plate.

[0029] The height adjustment device 10 comprises a height-adjustable adjustment slide 101, which is rotatably mounted on an adjustment spindle 104 in a lower spindle bearing 1041 and an upper spindle bearing 1042, and is height-adjustable by rotating the adjustment spindle 104. For this purpose, the adjustment slide 101 has an internal thread complementary to the external thread of the adjustment spindle 104, thus forming a type of spindle nut that is rotationally fixed and therefore changes height when the adjustment spindle 104 is rotated. Rotation of the adjustment slide 101 is prevented by its rigid connection to a carriage 1011, which can slide up and down in a substantially vertical direction on a substantially vertically arranged linear guide 102.

[0030] The rotation of the adjusting spindle 104 is effected by an adjusting drive 105 in the form of a servo motor, which – as can best be seen from the Figures 10and 12 As can be seen, a drive pulley 1051 drives a toothed belt 1052, which in turn drives an output pulley 1053 that rotates the adjusting spindle 104. In the other figures, the drive pulley 1051, the toothed belt 1052, and the output pulley 1053 are either concealed by housing parts or not visible due to the chosen view.

[0031] The plate holding unit 11 comprises a lifting carriage 111, which in a normal situation according to the Figures 3-5 and 7The lifting carriage 111 and the adjusting carriage 101 are removably mounted on the adjusting carriage 101. The lifting carriage 111 and the adjusting carriage 101 are connected to each other via a tension spring 14, which pulls the lifting carriage 111 towards the adjusting carriage 101. The lifting carriage 111 is provided on the left and right sides with a carriage 1111 and 1112, respectively, with the carriage 1111 sliding up and down on the linear guide 102 and the carriage 1112 sliding up and down on a substantially vertically arranged linear guide 103 parallel to the linear guide 102. The plate holding unit 11 is thus guided linearly by the two linear guides 102 and 103.

[0032] The lifting carriage 111 carries a clamping unit with a fixed clamping jaw 112 and a movable clamping jaw 113, between which a panel can be clamped. A panel edge sensor 122 is located below the fixed clamping jaw 112 for detecting a panel edge. The movable clamping jaw 113 can be adjusted relative to the fixed clamping jaw 112 by means of a clamping jaw drive, which is described below. Above the clamping jaws 112, 113, and the clamping jaw drive, the clamping unit has a cover 116 with an LED indicator 1161. The LED display 1161 can show the operating status of the plate lowering device 1, for example "currently lowering", "currently rising", "movable clamping jaw 113 currently adjusting", "lifting carriage 111 rests on adjusting carriage 101", "lifting carriage 111 has detached from adjusting carriage 101", etc.

[0033] Below the lifting carriage 111 is a clamping cylinder housing 117, which contains, among other things, a [missing information] in the Figure 9and 11 A visible pneumatic cylinder 118 is arranged for adjusting the movable clamping jaw 113. The pneumatic cylinder 118 can be supplied with and controlled by compressed air via a pneumatic hose 119, a releasable check valve 120, and a throttle valve 121; see in particular Fig. 7 .

[0034] How best to get from the Figures 3 and 5 As can be seen, the plate lowering device 1 has a rear housing wall 106 and two front housing wall parts 107 and 108, respectively. In the Figures 4 and 6 The plate lowering device 1 is shown without the two front housing wall parts 107, 108, which reveals the adjusting spindle 104 and a central support stop 109 for the plate holding unit 11 attached to the rear housing wall 106. The central support stop 109 is optionally removable, and in this case a lower stop 1090 for the plate holding unit 11 is provided.

[0035] Fig. 6 The plate lowering device 1, in contrast to the Figures 3-5 and 7 with lifting carriage 111 detached from the adjusting carriage 101. In Fig. 8 is detail B of Fig. 6 shown enlarged.

[0036] Starting from the one in the Figures 3-5 and 7 The situation depicted is the one in the Figure 6 and 8The situation described is reached in particular when the plate lowering device 1 encounters resistance during lowering with the lifting carriage 111 resting on the adjusting carriage 101. This occurs, for example, when a plate held by the plate holding unit 11 is placed on a support, such as the support rollers 25, or when the plate holding unit 11 is lowered onto the plate from above and stopped too late. Due to the upward force, the lifting carriage 111 has detached from the adjusting carriage 101, as the adjusting carriage 101 continued to move downwards while the lifting carriage 111 remained stationary. The kinematic connection between the plate holding unit 11 and the adjusting drive 105 is thus interrupted, since the movement of the adjusting carriage 101 is no longer transmitted to the lifting carriage 111. This corresponds to a freewheeling of the adjusting drive 105 with respect to the plate holding unit 11.

[0037] As soon as the adjusting carriage 101 comes into contact with the lifting carriage 111 again after an upward adjustment, a kinematic connection is re-established between the adjusting drive 105 and the lifting carriage 111, i.e., an upward movement generated by the adjusting drive 105 is transmitted directly to the lifting carriage 111 via the adjusting carriage 101.

[0038] In order to obtain optimal force distribution after placing a plate, for example plate 9, supported by the plate holding unit 11, onto the support rollers 25, it may be useful to briefly lift the adjusting carriage 101 again immediately after placing the plate, so that the lifting carriage 111 rests on the adjusting carriage 101 again.

[0039] In the in the in the Figure 6 and 8In the depicted situation, the tension spring 14, attached on the underside of the lifting carriage 111 and on the side of the adjusting carriage 101, is stretched and tensioned, pulling the lifting carriage 111 more strongly towards the adjusting carriage 101. However, as long as the plate 9, held by the plate holder 11, rests on the support rollers 25, thus creating an insurmountable counterforce to the spring force and the weight of the plate holder 11, the lifting carriage 111 does not move. The purpose of the tension spring 14 is, in particular, to move the lifting carriage 111 towards the adjusting carriage 101 when no insurmountable counterforce is present, but the weight of the plate holder 11 may be insufficient to overcome counterforces (such as frictional forces or supply lines pulling the plate holder 11 upwards). This is normally only the case if the plate holding unit 11 is not currently holding a plate.

[0040] Instead of the tension spring 14, the attracting force between adjusting slide 101 and lifting slide 111 can alternatively be generated by one or more magnets.

[0041] The Figures 9, 10 , 12 and 13 Figure 1 shows the plate lowering device 1 partially schematically from the side in various sectional views and in perspective from a rear oblique angle. Fig. 11 is detail C of Fig. 9 and in Fig. 14 detail D of Fig. 13 shown enlarged.

[0042] In Fig. 12 The figure shows how a plate 9 is clamped between the fixed clamping jaw 112 and the movable clamping jaw 113 and thus held by the plate holding unit 11, while at the same time resting on the support rollers 25.

[0043] From the Figure 9 and 11It is evident that the movable clamping jaw 113 is attached to a clamping slide 123, which is connected to a clamping cylinder piston 1180 of the pneumatic cylinder 118 by means of a clamping cable 124 guided over a pulley 125. A return spring 126 ensures that the clamping slide 123 with the movable clamping jaw 113 is biased away from the fixed clamping jaw 112. As can be seen in particular from Fig. 7 As can be seen, the pneumatic cylinder 118 can be supplied with and controlled by compressed air via a pneumatic hose 119, a releasable check valve 120, and a throttle valve 121. In this way, the clamping unit with the fixed clamping jaw 112 and the movable clamping jaw 113 can be adjusted by means of a pneumatic clamping jaw drive, which in turn can be controlled by the control device 4.

[0044] The pneumatic hose 119 is a supply line that runs from a stationary area of ​​the vertical panel saw to the panel holding unit 11. To prevent it from hanging loosely and undefined when the panel holding unit 1 is in various adjustment positions, the pneumatic hose 119 is guided into the interior of a chain 13 in a stationary upper area of ​​the panel lowering device 1, see in particular Figures 5 and 7 , which is deflected via two deflection pulleys 131, 132 to the pneumatic cylinder 118 inside the clamping cylinder housing 117, see in particular Figures 9-14, in which the chain 13 is partially represented schematically as a simple line. While the upper deflection pulley 131 is fixedly mounted near the upper end of the plate lowering device 1, the lower deflection pulley 132 is movably and suspended. The pivot axis 1320 of the lower deflection pulley 132 is mounted in an angle bracket 133. The angle bracket 133 is connected to one end of a tension spring 139, the other end of which is connected to a mounting element 138 attached to the rear housing wall 106. The tension spring 139 pulls the angle bracket 133 downwards, thus pre-tensioning the movably mounted lower deflection pulley 132 in the direction away from the upper deflection pulley 131. This results in the higher the position of the plate holding unit 11, the greater the distance between the two deflection rollers 131, 132, whereby the chain 13 is always reasonably taut, i.e., it does not simply hang loosely and undefined.Such an arrangement of the chain 13 deflected over two deflection pulleys 131, 132 is also relatively space-saving.

[0045] Out of Fig. 14 It is evident that a (preferably inductive) release sensor 114 is arranged in the lifting carriage 111 of the plate holding unit 11, which detects the release of the lifting carriage 111 from the adjustment carriage 101. This makes it possible to react to the release of the lifting carriage 111 from the adjustment carriage 101 and, for example, to stop the adjustment drive 105 or even briefly move it in the opposite direction until the adjustment carriage 101 is again in contact with the lifting carriage 111 and the plate holding unit 11 is once again supported by the adjustment carriage 101 via the lifting carriage 111.

[0046] In a stationary upper area of ​​the plate lowering device 1, a (preferably inductive) reference sensor 115 is also arranged, with which the position of the plate holding unit 11 can be determined.

Claims

1. Vertical panel saw having a frame (2), a saw unit (3) movably arranged on the frame (2), and a panel-lowering device (1, 1', 1"), wherein the panel-lowering device (1, 1', 1") comprises a height-adjustment device (10) having an adjustment drive (105) and a panel-holding unit (11, 11', 11") for holding a panel (9; 90), which panel-holding unit is height-adjustably arranged on the height-adjustment device (10), characterised in that the height-adjustment device (10) comprises a height-adjustable adjustment carriage (101) and the panel-holding unit (11, 11', 11") comprises a lifting carriage (111), and the panel-holding unit (11, 11', 11") is kinematically connected to the adjustment drive (105) via a freewheel, the freewheel interrupting the kinematic connection between panel-holding unit (11, 11', 11") and adjustment drive (105) when a panel (9; 90) held by the panel-holding unit (11, 11', 11") is placed on a support.

2. Vertical panel saw according to claim 1, characterised in that the lifting carriage (111) is separably supported on the adjustment carriage (101).

3. Vertical panel saw according to claim 1 or 2, characterised in that the height-adjustment device (10) comprises an adjustment spindle (104) which is rotatable by means of the adjustment drive (105), and the adjustment carriage (101) is arranged on the adjustment spindle (104) and is adjustable in height by rotation of the adjustment spindle (104).

4. Vertical panel saw according to any one of claims 1 to 3, characterised in that the height-adjustment device (10) comprises at least one linear guide (102, 103) on which the panel-holding unit (11, 11', 11") is linearly guided.

5. Vertical panel saw according to any one of claims 2 to 4, characterised in that the panel-holding unit (11, 11', 11") has a separation sensor (114) which detects the separation of the lifting carriage (111) from the adjustment carriage (101).

6. Vertical panel saw according to any one of claims 1 to 5, characterised in that the panel-holding unit (11, 11', 11") is a clamping unit having a fixed clamping jaw (112) and a movable clamping jaw (113), between which a panel (9; 90) can be clamped, the movable clamping jaw (113) being movable, preferably linearly guided, towards the fixed clamping jaw (112) by means of a clamping jaw drive, preferably a pneumatic clamping jaw drive.

7. Vertical panel saw according to any one of claims 1 to 6, characterised in that at least one supply line of the panel-holding unit (11, 11', 11") is guided via two deflection rollers (131, 132) from a static region of the vertical panel saw to the panel-holding unit (11, 11', 11"), one of the two deflection rollers (131, 132) being arranged to be movable in such a way that the higher the position of the panel-holding unit (11, 11', 11"), the greater the spacing between the two deflection rollers (131, 132), the movably arranged deflection roller (132) preferably being pretensioned in a direction away from the other deflection roller (131).

8. Vertical panel saw according to any one of claims 1 to 7, characterised in that the panel-lowering device (1, 1', 1") comprises pulling means, preferably a tension spring (14) or at least one magnet, which pull the lifting carriage (111) towards the adjustment carriage (101).

9. Vertical panel saw according to any one of claims 1 to 8, characterised in that it comprises two or more panel-lowering devices (1, 1', 1") which are preferably adjustable synchronously.

10. Vertical panel saw according to any one of claims 1 to 9, characterised in that it comprises a control device (4) for controlling the panel-lowering device (1, 1', 1") or the two or more panel-lowering devices (1, 1', 1"), as the case may be.