阅读说明：本技术 一种木材刨片机端刀安装用防位置偏移分切切刀 (Cutter is cut with preventing offset to installation of timber planer end sword ) 是由 芮正兴 于 2021-07-28 设计创作，主要内容包括：本发明涉及切刀技术领域,具体为一种木材刨片机端刀安装用防位置偏移分切切刀,包括切割台,所述切割台表面中间位置处开设有第一开槽,所述切割台表面一侧开设有滑槽,所述第一开槽内部设置有切割刀片,所述切割台靠近滑槽一侧表面顶端设置有待切板材,所述切割台底端四个顶角处皆设置有支撑柱,且支撑柱底端内部开设有第一槽孔,所述支撑柱底端内部设置有调节杆,且调节杆顶端内部开设有第二槽孔,所述调节杆底端固定连接有底块,所述切割台底端靠近第一开槽一侧表面设置有伺服电机。本发明通过伺服电机的转动带动夹板向靠近切割刀片一侧移动,实现对切割刀片的固定操作,从而有效防止在待切板材与切割刀片接触时,切割刀片发生位置偏移。(The invention relates to the technical field of cutters, in particular to a position deviation prevention slitting cutter for installing a cutter at the end of a wood slicing machine, which comprises a cutting table, wherein a first groove is formed in the middle position of the surface of the cutting table, a sliding groove is formed in one side of the surface of the cutting table, a cutting blade is arranged in the first groove, a plate to be cut is arranged at the top end of the surface of one side, close to the sliding groove, of the cutting table, supporting columns are arranged at four top corners of the bottom end of the cutting table, a first slotted hole is formed in the bottom end of each supporting column, an adjusting rod is arranged in the bottom end of each supporting column, a second slotted hole is formed in the top end of each adjusting rod, a bottom block is fixedly connected to the bottom end of each adjusting rod, and a servo motor is arranged on the surface, close to the first groove, of the bottom end of the cutting table. The servo motor rotates to drive the clamping plate to move towards one side close to the cutting blade, so that the cutting blade is fixed, and the position deviation of the cutting blade is effectively prevented when a plate to be cut is in contact with the cutting blade.)

1. The utility model provides a cutter is cut with preventing offset to installation of timber flaking machine end sword which characterized in that includes:

the cutting table (110), a first slot (111) is formed in the middle position of the surface of the cutting table (110), a sliding groove (112) is formed in one side of the surface of the cutting table (110), a cutting blade (120) is arranged inside the first slot (111), a plate to be cut (130) is arranged on the top end of the surface of one side, close to the sliding groove (112), of the cutting table (110), supporting columns (140) are arranged at four top corners of the bottom end of the cutting table (110), first slot holes (141) are formed in the bottom end of each supporting column (140), an adjusting rod (150) is arranged inside the bottom end of each supporting column (140), second slot holes (151) are formed in the top end of each adjusting rod (150), a bottom block (160) is fixedly connected to the bottom end of each adjusting rod (150), a servo motor (170) is arranged on the surface of one side, close to the first slot (111), and an output end of each servo motor (171) is connected to the cutting table (110), the mounting plate (180) is arranged outside the servo motor (170), and the top end of the mounting plate (180) is fixedly connected with the bottom end of the cutting table (110);

the anti-deviation mechanism comprises a rotating ring (210), the rotating ring (210) is arranged outside one side, away from the servo motor (170), of the output shaft (171), and second slots (211) are formed in the inner portions of the upper end and the lower end of the rotating ring (210).

2. The wood planer end cutter installation of claim 1 is with preventing position drift cutting cutter, characterized by: the utility model discloses a hydraulic pressure oil pump, including second fluting (211), first connecting block (220) is equipped with to inside inserting of second fluting (211), and first connecting block (220) is connected with output shaft (171) fixed surface, the first connecting block (220) is kept away from the first fixed block (230) of all fixedly connected with of rotating ring (210) one end, servo motor (170) one side is kept away from to rotating ring (210) is provided with first threaded rod (240), and first threaded rod (240) and rotating ring (210) fixed connection, first threaded rod (240) is all fixedly connected with second connecting block (241) in both ends from top to bottom servo motor (170) one side, and first threaded rod (240) surface and second connecting block (241) inner wall pass through threaded connection, servo motor (170) one side outside is kept away from to first threaded rod (240) is provided with solid fixed cylinder (250), first connecting block (240) one end is kept away from to second connecting block (241) all fixedly connected with clamping piece (260), and two sides of the plate to be cut (130) are provided with limiting mechanisms.

3. The wood planer end cutter installation of claim 1 is with preventing position drift cutting cutter, characterized by: four apex angles on the surface of the cutting table (110) are wrapped with anti-collision pads (113), and the anti-collision pads (113) are made of sponge materials.

4. The wood planer end cutter installation of claim 2 is with preventing position drift cutting cutter, characterized by: a protective pad (261) is glued on the surface of one side, close to the cutting blade (120), of the clamping piece (260), and the protective pad (261) is made of a rubber material.

5. The wood planer end cutter installation of claim 2 is with preventing position drift cutting cutter, characterized by: stop gear includes limiting plate (310), it all is provided with limiting plate (310) to wait to cut sheet material (130) both sides, limiting plate (310) both sides bottom all fixedly connected with second fixed block (320), second fixed block (320) are inside to wear to be equipped with second threaded rod (330), and second threaded rod (330) surface and second fixed block (320) inner wall threaded connection, second threaded rod (330) one side is kept away from inside second fixed block (320) and is provided with slide bar (340), second threaded rod (330) are kept away from and are waited to cut sheet material (130) one side fixedly connected with carousel (350), carousel (350) one side fixed surface is connected with rocker (360), limiting plate (310) are close to and are waited to cut sheet material (130) one side and are provided with buffer gear.

6. The wood planer end tool installation of claim 5 is with preventing position drift cutting cutter, characterized by: the outside of rocker (360) is provided with slipmat (361), and the surface of slipmat (361) is provided with the lug.

7. The wood planer end tool installation of claim 5 is with preventing position drift cutting cutter, characterized by: buffer gear includes pulley (410), it is provided with pulley (410) to wait to cut sheet material (130) and be close to limiting plate (310) side surface, the equal fixedly connected with third fixed block (420) in surface of both ends intermediate position department about pulley (410), third fixed block (420) are kept away from and are waited to cut sheet material (130) one side and are provided with sleeve (430), sleeve (430) are kept away from third fixed block (420) one side and are provided with telescopic link (440), and telescopic link (440) one side stretches into inside sleeve (430), the surface of sleeve (430) and telescopic link (440) all is provided with first spring (450), and first spring (450) both sides fixed connection respectively is on the surface of third fixed block (420) and limiting plate (310), support column (140) surface is provided with leveling mechanism.

8. The wood planer end cutter installation of claim 1 is with preventing position drift cutting cutter, characterized by: leveling mechanism includes inserted bar (510), inserted bar (510) are all worn to be equipped with inside first slotted hole (141) and second slotted hole (151), both ends are all fixedly connected with third connecting block (520) about support column (140) one side are kept away from in inserted bar (510), support column (140) are close to third connecting block (520) one side and are provided with second spring (540), and the surface at third connecting block (520) and support column (140) is fixed respectively to second spring (540) both sides.

9. The wood planer end tool installation of claim 8 is with preventing position drift cutting cutter, characterized by: the adjusting block (530) is fixedly connected to one side, far away from the supporting column (140), of the inserted rod (510), the anti-skidding blocks (531) are fixedly connected to the surface of the adjusting block (530), and the anti-skidding blocks (531) are distributed on the surface of the adjusting block (530) at equal intervals.

Technical Field

The invention relates to the technical field of cutters, in particular to a position deviation preventing slitting cutter for installing a cutter at the end of a wood slicing machine.

Background

The cutter that is used for cutting is at the wood processing in-process, because timber self size is different, in order to make timber can better adapt to people's user demand, just need to hold up the size of timber and cut, make it have specific specification and usefulness, along with the development of modern wood processing trade, can know that present cutter basically satisfies people's demand, but still has some problems.

The first problem is that: the existing cutter basically rotates by means of motor drive, so that the cutter close to the wood realizes the cutting of the wood, and the cutter is in a high-speed rotating state when the wood is contacted with the cutter, so that the wood is close to the cutter, the cutter is easy to shift under the collision generated by contact, the cutting is not accurate, and the practicability of the device is reduced;

the second problem is that: carry timber among the prior art and usually be through the handheld timber of operating personnel, be close to the cutter with timber gradually, realize cutting operation, lack spacing to timber, this kind of operation requires highly to operating personnel's proficiency, the new hand is when actual operation, can be because the experience is not enough, make timber move the orbit not remove according to the route of surveying in advance, it is not accurate to lead to the cutting, and extravagant material, the practicality of device has been reduced, consequently need for a timber planer end sword installation with preventing that the position excursion cuts the cutter and solve above-mentioned problem urgently.

Disclosure of Invention

In order to overcome the above technical problems, an object of the present invention is to provide a position deviation preventing slitting cutter for installing an end cutter of a wood planer, so as to solve the problems in the prior art that the cutter is easy to shift when contacting with wood, and a limit mechanism is not needed when conveying wood.

In order to achieve the purpose, the invention provides the following technical scheme: the utility model provides a cutter is cut with preventing offset to installation of timber flaking machine end sword, includes:

the cutting table is characterized in that a first slot is formed in the middle of the surface of the cutting table, a sliding groove is formed in one side of the surface of the cutting table, a cutting blade is arranged in the first slot, a plate to be cut is arranged at the top end of the surface of one side, close to the sliding groove, of the cutting table, supporting columns are arranged at four top corners of the bottom end of the cutting table, a first slot hole is formed in the bottom end of each supporting column, an adjusting rod is arranged in the bottom end of each adjusting rod, a second slot hole is formed in the top end of each adjusting rod, a bottom block is fixedly connected to the bottom end of each adjusting rod, a servo motor is arranged on the surface, close to one side of the first slot, of the bottom end of the cutting table, the output end of the servo motor is connected with an output shaft, a mounting plate is arranged outside the servo motor, and the top end of the mounting plate is fixedly connected with the bottom end of the cutting table;

prevent excursion mechanism, including the swivel becket, the output shaft is kept away from servo motor one side outside and is provided with the swivel becket, the second fluting has all been seted up to both ends inside about the swivel becket, and the design can effectively prevent when waiting to cut sheet material and cutting blade contact like this, and cutting blade takes place the skew to cause the inaccurate condition of cutting.

Preferably, a first connecting block is inserted into the second slot, the first connecting block is fixedly connected with the surface of the output shaft, a first fixing block is fixedly connected to one end, away from the rotating ring, of the first connecting block, a first threaded rod is arranged on one side, away from the servo motor, of the rotating ring, the first threaded rod is fixedly connected with the rotating ring, a second connecting block is fixedly connected to the upper end and the lower end of one side of the first threaded rod Yuan Rui servo motor, the surface of the first threaded rod is in threaded connection with the inner wall of the second connecting block, a fixing barrel is arranged outside one side, away from the servo motor, of the first threaded rod, a clamping piece is fixedly connected to one end, away from the first threaded rod, of the second connecting block, limiting mechanisms are arranged on two sides of the plate to be cut, and therefore, when the servo motor rotates to drive the cutting blade to rotate, two groups of clamping pieces are driven to move towards one side close to the cutting blade, the cutting operation can be realized while the cutting is realized.

Preferably, four apex angle departments on cutting bed surface all wrap up and are provided with the crash pad, and the crash pad is made by sponge material, and the design is favorable to protecting operating personnel like this.

Preferably, a protection pad is glued on the surface of one side, close to the cutting blade, of the clamping piece, and the protection pad is made of a rubber material, so that the protection of the cutting blade is facilitated.

Preferably, stop gear includes the limiting plate, it all is provided with the limiting plate to wait to cut panel both sides, the equal fixedly connected with second fixed block in limiting plate both sides bottom, the second threaded rod is worn to be equipped with inside the second fixed block, and second threaded rod surface and second fixed block inner wall threaded connection, the inside second threaded rod one side of keeping away from of second fixed block is provided with the slide bar, the second threaded rod is kept away from and is waited to cut panel one side fixedly connected with carousel, carousel one side fixed surface is connected with the rocker, the limiting plate is close to and is provided with buffer gear on one side of waiting to cut panel, and the design is favorable to waiting to cut panel according to the route promotion of predesigned like this, realizes accurate cutting.

Preferably, the rocker is externally provided with a non-slip mat, and the surface of the non-slip mat is provided with a convex block, so that the design is favorable for adjusting the rocker.

Preferably, buffer gear includes the pulley, it is provided with the pulley to wait to cut panel to be close to limiting plate side surface, the equal fixedly connected with third fixed block in surface of both ends intermediate position department about the pulley, the third fixed block is kept away from and is waited to cut panel one side and is provided with the sleeve, the sleeve is kept away from third fixed block one side and is provided with the telescopic link, and telescopic link one side stretches into inside the sleeve, the surface of sleeve and telescopic link all is provided with first spring, and first spring both sides difference fixed connection is on the surface of third fixed block and limiting plate, the support column surface is provided with leveling mechanism, and the design has like this to do benefit to and makes the pulley hug closely waiting to cut panel surface, realizes waiting to cut the spacing of panel.

Preferably, leveling mechanism includes the inserted bar, the inserted bar is all worn to be equipped with inside first slotted hole and the second slotted hole, the inserted bar is kept away from the equal fixedly connected with third connecting block in both ends about support column one side, the support column is close to third connecting block one side and is provided with the second spring, and the second spring both sides are fixed respectively on the surface of third connecting block and support column, and the design can realize the fine setting to the height like this.

Preferably, the inserted bar is kept away from support column one side fixedly connected with regulating block, regulating block fixed surface is connected with the non slipping spur, and the non slipping spur is the equidistance and distributes on the surface of regulating block, and the design is favorable to pulling the inserted bar like this.

Compared with the prior art, the invention has the beneficial effects that:

1. the device is provided with a rotating ring, a first connecting block, a first fixing block, a first threaded rod, a fixing barrel and clamping pieces, through the design, the device is provided with an anti-deviation mechanism, when a cutting blade is contacted with a plate to be cut, the problem that the cutting blade is not accurate due to the deviation of the position can be effectively prevented, the device is driven to rotate by switching on a servo motor, so that the rotating ring and the first threaded rod are driven to rotate under the action of the first connecting block, because the surface of the first threaded rod is in threaded connection with the inner wall of a second connecting block, when the first threaded rod rotates, two groups of second connecting blocks both move to one side close to the cutting blade, the clamping pieces are driven to move to one side close to the cutting blade until a protective pad is attached to the surface of the cutting blade, the cutting blade can be driven to rotate when being fixed, and the cutting operation is realized, the practicability and linkage of the device are improved.

2. The device is provided with the limiting plate, the second fixed block, the second threaded rod, the slide bar, carousel and rocker, through the above-mentioned design, make the device possess stop gear, when treating cut panel and carry, it removes according to predetermined route to enable to treat that cut panel is strict, thereby it is more accurate to make the cutting, drive carousel and second threaded rod through rotating the rocker and rotate, under second threaded rod surface and second fixed block inner wall threaded connection's effect, make two sets of limiting plates all to being close to and waiting to cut panel one side and remove, the telescopic link is to the inside shrink of sleeve this moment, first spring is in the elastic compression state, make the pulley hug closely and be waiting to cut the panel surface, realize the spacing operation to waiting to cut panel, the stability of device has been improved.

Drawings

FIG. 1 is a perspective view of the present invention;

FIG. 2 is a perspective view of a partial structure of the anti-shifting mechanism of the present invention;

FIG. 3 is an exploded view of a portion of the anti-migration mechanism of the present invention;

FIG. 4 is a perspective view of a partial structure of the limiting mechanism of the present invention;

FIG. 5 is a perspective view of a partial structure of the leveling mechanism according to the present invention;

FIG. 6 is an enlarged schematic view of the structure at A in FIG. 3 according to the present invention;

FIG. 7 is an enlarged schematic view of the structure at B in FIG. 4 according to the present invention;

FIG. 8 is an enlarged schematic view of the structure of FIG. 4 at C in accordance with the present invention;

fig. 9 is an enlarged schematic view of the structure at D in fig. 5 according to the present invention.

In the figure: 110. cutting table; 111. a first slot; 112. a chute; 113. an anti-collision pad; 120. a cutting blade; 130. a plate to be cut; 140. a support pillar; 141. a first slot; 150. adjusting a rod; 151. a second slot; 160. a bottom block; 170. a servo motor; 171. an output shaft; 180. mounting a plate; 210. a rotating ring; 211. a second slot; 220. a first connection block; 230. a first fixed block; 240. a first threaded rod; 241. a second connecting block; 250. a fixed cylinder; 260. a clip; 261. a protection pad; 310. a limiting plate; 320. a second fixed block; 330. a second threaded rod; 340. a slide bar; 350. a turntable; 360. a rocker; 361. a non-slip mat; 410. a pulley; 420. a third fixed block; 430. a sleeve; 440. a telescopic rod; 450. a first spring; 510. inserting a rod; 520. a third connecting block; 530. an adjusting block; 531. anti-skid blocks; 540. a second spring.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Referring to fig. 1-9, an embodiment of the present invention is shown: the utility model provides a cutter is cut with preventing offset to installation of timber flaking machine end sword, includes:

the cutting table 110, a first slot 111 is formed in the middle of the surface of the cutting table 110, a sliding groove 112 is formed in one side of the surface of the cutting table 110, a cutting blade 120 is arranged inside the first slot 111, a plate 130 to be cut is arranged on the top end of the surface of one side, close to the sliding groove 112, of the cutting table 110, supporting columns 140 are arranged at four top corners of the bottom end of the cutting table 110, a first slot 141 is formed in the bottom end of each supporting column 140, an adjusting rod 150 is arranged inside the bottom end of each supporting column 140, a second slot 151 is formed in the top end of each adjusting rod 150, a bottom block 160 is fixedly connected to the bottom end of each adjusting rod 150, a servo motor 170 is arranged on the surface of one side, close to the first slot 111, the output end of the servo motor 170 is connected with an output shaft 171, a mounting plate 180 is arranged outside the servo motor 170, and the top end of the mounting plate 180 is fixedly connected with the bottom end of the cutting table 110;

prevent excursion mechanism, including swivel 210, output shaft 171 is kept away from servo motor 170 one side outside and is provided with swivel 210, and second fluting 211 has all been seted up to swivel 210 upper and lower both ends inside, through this design, makes to rotate when servo motor 170 rotates, just can realize the fixed operation to cutting blade 120, prevents that it from taking place the skew of position when with waiting to cut sheet material 130 contact, has improved the stability and the practicality of device.

The first connecting block 220 is inserted into the second slot 211, the first connecting block 220 is fixedly connected with the surface of the output shaft 171, one end of the first connecting block 220, which is far away from the rotating ring 210, is fixedly connected with a first fixing block 230, one side of the rotating ring 210, which is far away from the servo motor 170, is provided with a first threaded rod 240, the first threaded rod 240 is fixedly connected with the rotating ring 210, the upper end and the lower end of one side of the first threaded rod 240 Yuan servo motor 170 are fixedly connected with a second connecting block 241, the surface of the first threaded rod 240 is connected with the inner wall of the second connecting block 241 through threads, the outside of one side of the first threaded rod 240, which is far away from the servo motor 170, is provided with a fixing cylinder 241, one end of the second connecting block, which is far away from the first threaded rod 240, is fixedly connected with a clamping piece 260, two sides of the plate to be cut 130 are provided with limiting mechanisms, through the design, the device is provided with an anti-deviation mechanism, when the cutting blade 120 is in contact with the plate to be cut 130, the situation that the cutting blade 120 deviates can not occur, so that the cutting operation is more accurate, and the practicability of the device is improved.

Four apex angle departments in cutting table 110 surface all wrap up and are provided with crashproof pad 113, and crashproof pad 113 is made by sponge material, through this design, thereby can prevent effectively that operating personnel's abdomen from hitting four apex angle departments of device injured, has improved the protectiveness of device.

The protection pad 261 is glued to the surface of the clamping piece 260 close to one side of the cutting blade 120, the protection pad 261 is made of rubber materials, the protection of the cutting blade 120 is facilitated through the design, and through the design, when the protection pad 261 contacts the cutting blade 120, the pressure between contact surfaces can be relieved, and the protection performance of the device is improved.

Stop gear includes limiting plate 310, treat that cut sheet 130 both sides all are provided with limiting plate 310, limiting plate 310 both sides bottom is the second fixed block 320 of all fixedly connected with, second threaded rod 330 is worn to be equipped with inside the second fixed block 320, and second threaded rod 330 surface and the inner wall threaded connection of second fixed block 320, the inside second threaded rod 330 one side of keeping away from of second fixed block 320 is provided with slide bar 340, second threaded rod 330 is kept away from and is treated cut sheet 130 one side fixedly connected with carousel 350, carousel 350 one side fixed surface is connected with rocker 360, limiting plate 310 is close to and is provided with buffer gear on one side of treating cut sheet 130, through this design, make the device possess stop gear, when treating cut sheet 130 and carry, enable to treat that cut sheet 130 removes according to the route of presetting, make the cutting more accurate, the practicality of device has been improved.

The outside of rocker 360 is provided with slipmat 361, and the surface of slipmat 361 is provided with the lug, through this design, when pulling slipmat 361, can effectively prevent to pull the condition that the in-process appears taking off the hand, has improved the stability of device.

The buffer mechanism comprises a pulley 410, the pulley 410 is arranged on the surface of one side of the plate to be cut 130 close to the limiting plate 310, the surface of the middle position of the upper end and the lower end of the pulley 410 is fixedly connected with a third fixing block 420, the side of the third fixing block 420 far away from the plate to be cut 130 is provided with a sleeve 430, the side of the sleeve 430 far away from the third fixing block 420 is provided with an expansion link 440, one side of the expansion link 440 extends into the sleeve 430, the surfaces of the sleeve 430 and the expansion link 440 are provided with a first spring 450, the two sides of the first spring 450 are respectively and fixedly connected with the surfaces of the third fixing block 420 and the limiting plate 310, the surface of the supporting column 140 is provided with a leveling mechanism, by the design, the pressure between the plate to be cut 130 and the pulley 410 can be reduced, because the periphery of the plate to be cut 130 is mostly irregular, the design can enable the pulley 410 to be always in a state of being tightly attached to the plate to be cut 130, thereby better realizing the limiting operation, the stability of the device is improved.

The leveling mechanism comprises an inserting rod 510, the inserting rod 510 penetrates through the inner portions of the first slotted hole 141 and the second slotted hole 151, the inserting rod 510 is far away from the third connecting block 520 fixedly connected with the upper end and the lower end of one side of the supporting column 140, the supporting column 140 is provided with a second spring 540 close to one side of the third connecting block 520, and the two sides of the second spring 540 are respectively fixed on the surfaces of the third connecting block 520 and the supporting column 140.

The adjusting block 530 is fixedly connected to one side, far away from the supporting column 140, of the inserting rod 510, the anti-slip blocks 531 are fixedly connected to the surface of the adjusting block 530, the anti-slip blocks 531 are distributed on the surface of the adjusting block 530 at equal intervals, and through the design, the position of the inserting rod 510 is convenient to adjust, and the convenience of the device is improved.

The working principle is as follows: the servo motor 170 is switched on to operate and rotate, so that the rotating ring 210 and the first threaded rod 240 are driven to rotate under the action of the first connecting block 220, and because the surface of the first threaded rod 240 is in threaded connection with the inner wall of the second connecting block 241, when the first threaded rod 240 rotates, the two groups of second connecting blocks 241 move towards one side close to the cutting blade 120, so that the clamping pieces 260 are driven to move towards one side close to the cutting blade 120 until the protective pads 261 are attached to the surface of the cutting blade 120, the cutting blade 120 can be driven to rotate while the cutting blade 120 is fixed, and the cutting operation is realized;

rotating the rocker 360 to drive the turntable 350 and the second threaded rod 330 to rotate, under the effect of threaded connection between the surface of the second threaded rod 330 and the inner wall of the second fixed block 320, the two sets of limiting plates 310 move to the side close to the plate 130 to be cut, at the moment, the telescopic rod 440 contracts towards the inside of the sleeve 430, the first spring 450 is in an elastic compression state, the pulley 410 is tightly attached to the surface of the plate 130 to be cut, the limiting operation on the plate 130 to be cut is realized, and the operation is finished.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. Any reference sign in a claim should not be construed as limiting the claim concerned.