US3465798A - Ring barker - Google Patents

Description

P 1969 F. J. CAMERON 3,465,798

RING BARKER Filed Sept. 25. 1967 v 3 Sheets-Sheet 1 7 2- Frank J. CAMEROE'J,

Age

Sept. 9, 1969 F. J. CAMERON nine BARKER 3 Sheets-Sheet 2 Filed Sept. 25. 1967 Frank J. CAMERON;

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Agent Sept. 9, 1969 F. J. CAMERON 3,455,798

RING BARKER Filed Sept. 25. 1967 3 Sheets-Sheet 3 Frank J. CAMERON,

Inventor United States Patent 3,465,798 RING BARKER Frank J. Cameron, North Vancouver, British Columbia, Canada, assignor, by mesne assignments, to Kal-Pac Engineering Ltd., Vancouver, British Columbia, Canada, a corporation of British Columbia Filed Sept. 25, 1967, Ser. No. 670,371 Claims priority, application Great Britain, Sept. 28, 1966, 43,273/ 66 Int. Cl. B271 1/00 U.S. Cl. 144-208 16 Claims ABSTRACT OF THE DISCLOSURE A rotating ring log barker with pneumatic cylinders operating the abrader arms, supply air from an epicycically driven ring mounted rotary pump. An idle air circuit controlled by a one way relief valve opening at a determinate pressure. A ring mounted oil tank with centrifugal oil supply for sealing the pump, and a centrifugal oil separator removing oil from the air supply returning it to the tank. Remote control of the abrader arms and of the determinate pressure opening the relief valve.

BACKGROUND OF THE INVENTION The invention relates to an improved mechanical rotating ring barker, of a type wherein abrader arms mounted upon the ring are urged into engagement with bark of a log by double acting pneumatic cylinder means.

In some prior barkers of this kind, air under pressure is provided by means including a pump mounted on the rotating ring. The use of a rotary vane pump or compressor has certain advantages, but to attain a suitable pressure which, typically might be 80 lb./in. leakage problems are encountered. While rotary pumps are now available with improved oil sealing, in previous apparatus as known to the applicant, the use of an oil sealed rotating vane pump has resulted in undesirable oil content in the compressed air. Not only is the oil consumption excessive, but also oil in the air lines tends to impede the action of the pneumatic cylinder.

OUTLINE OF THE INVENTION The above and other difficulties and disadvantages are reduced, in the apparatus of the present invention, to an extent which results in a practical and commercially feasible barker.

Accordingly, the present invention provides, a rotating ring barker apparatus having an abrader arm, the arm being actuated by double acting pneumatic cylinder means, rotary pump means supplying air to the cylinder, and an oil tank to supply oil for sealing the pump, and for lubrication, the foregoing being secured to the rotating ring; and in combination with the foregoing, a line from an air intake to the pump having a one way valve permitting air to flow only from the intake to the pump; an outlet line from the pump to a control valve admitting supply air to the cylinder; a return line from the supply line to the inlet line upstream from the one way valve; and a normally closed one way relief valve adapted to open at a determinate pressure. The foregoing structure provides that when the one way relief valve is open, air from the pump can circulate freely without performing work the pump being operated by rotation of the ring.

The rotating ring is hollow, and is made airtight to provide an air receiver or reservoir in the outlet line between the pump and the return line.

The invention is further characterized by an oil separator in an outlet line from the pump, constructed and arranged so that the extracted oil is returned to the oil 'ice tank. The oil separator includes; a dome like structure having a base and an axis, the separator being mounted on the rotating ring with the axis generally radial, an apex of the dome being remote from the centre of the ring; and by an outlet fitting placed at the apex of the dome for attachment of a pipe leading to the oil tank. Wet air, that is air containing oil from the pump, enters the hollow dome like structure tangentially so thatthe air pressure approaching lb./in. -the entering wet air is given a swirling motion from tangential impingement upon an inner wall of the hollow dome. An air outlet pipe extends through the base of the dome for a distance above the position of entry of the wet air. As the ring may be rotating at two or three hundred revolutions per minute, the swirling oil mist and droplets are urged in a spiral path by centrifugal force collecting at the apex of the dome and discharging through the dome apex outlet. Thus the air from which oil has been removed passes through the air outlet pipe aforesaid to the air receiver. The oil is not entirely removed, nor is it desirable that this should be the case for the residual oil acts to lubricate pistons of the pneumatic abrader arm actuating means, and for the valves, thus rendering it unnecessary to have a separate lubricating system for these elements.

The invention further provides for the pump to be epicyelically driven from a fixed, or static, pulley mounted coaxially with the rotating ring, V-belt means cooperating with the static pulley and a drive pulley of the pump, giving the epicylic drive. Equivalent drive can be effected by epicylic gear means, but the means above are preferred, being simple and effective.

In combination with the foregoing, the invention also provides a solenoid control valve, the solenoid being controlled electrically by remote means described below.

The one way relief valve opens at a particular pres sure, a valve the opening pressure of which can be adjusted is preferred, and the invention further provides remote electrical control for an adjustable valve, as hereinafter particnlarized.

These and other attributes of the improved ring braker are further described below in a detail description of an example of preferred embodiment of the invention.

DESCRIPTION OF THE DRAWINGS FIGURE 1 is a perspective front view of a ring barker apparatus according to the present invention,

FIGURE 2 is a perspective rear view, at larger scale, of the barker shown in FIGURE 1,

FIGURE 3 is a front elevation of a barker ring assembly with some parts omitted,

FIGURE 4 is a simplified diagrammatic side elevation of FIGURE 3 illustrating pump mounting and drive means, slip ring position, and having electrical connections added,

FIGURE 5 is a diagram showing operative interconnection between ring mounted elements of the barker, individual elements being shown at different scales,

FIGURE 6 is a detail of the centrifugal oil separator, parts being broken away to show interior construction,

FIGURE 7 is a fragmented part section on 7-7 of FIGURE 6.

A detail description following is related to the figures above, and describes preferred structure embodying the invention which, however, is capable of expression in structure other than that particularly described and illustrated.

DESCRIPTION OF THE PREFERRED EMBODIMENT General description related to FIGURES 1 and 2 A barker apparatus is indicated generally by the numeral 10. A frame 11 has rolls 12 obviously journalled on shafts of brackets secured to the frame. A hollow drum 13, known in the trade as a ring and hereinafter so called, is designated by the numeral 13 and the ring being rotatable within the frame supported by the rolls 12, and having a central opening for passage of a log therethrough. Abrader arms 14 are swingingly mounted on a front end wall 15 of the ring.

Log advancing means indicated generally by the numeral 16 include a front drive pair 16.1 and a rear drive pair 16.2, linkage 17 and associated structure are adapted to move the drive pair 16.2 from a position shown in FIGURE 2 where elements of the pair 16.2 are widely separated, to a position shown in FIGURE 1 where the said elements are close to one another, or to an intermediate position. The drive pair 16.1 is also movable in the same way by the same means. A prime mover 18 seen in FIGURE 1 only, suitably an internal combustion engine, has a drive pulley 19 operatively connected by a belt 21 passing around a belt groove 13.1 of an outer periphery of the ring, so that the ring is driven by the prime mover. A suitable speed of rotation is two or three hundred r.p.m. as aforesaid.

The abrader arms 14 are swingable, by means later described, from a position shown in FIGURE 2 where hooked cutting ends of the arms are in a closed position close to one another, to an open position shown in FIG- URE 1 the abrader arms are retracted so that the cutting ends are widely spaced from one another. A rotary pump 23 provides air under pressure to operate means effecting motion of the abrader arms as aforesaid, provision being made to hold the arms at an intermediate position according to the diameter of a log being barked. A cylindrical wall 24 concentric with the drum outer periphery defines the central opening.

In operation, a log to be barked is advanced by ancillary means, not shown, to be engaged by the front drive pair 16.1 the relative position of the elements of which is adjusted, according to the diameter of the log, to effect proper drive. The abrader arms are adjusted so that, as the log advances, the cutting edges rotating with the ring engage the log periphery so removing the bark.

Barkers within the description above are well known, it is therefore deemed that further general description is unnecessary for understanding, by those skilled in the art, of structure described below in detail.

Description of FIGURE 3, with further reference to FIGURE 2 In FIGURE 3, a front wall of the ring 13 is designated by the numeral 25, a double acting pneumatic cylinder assembly 26 being secured to the front wall. The cylinder assembly includes a piston rod 27 an outer end of which is rotatably secured to an end of a cranked arm 28 of the abrader 14, so that extension and retraction of the piston rod causes the abrader arm 14 to swing about a stud 29 from an outer full line position 14, the open position, the closed position shown in broken outline at 14.1. Several abrader arms are provided, typically five or six. Each abrader arm is constructed and arranged as aforesaid for swinging motionprovision for independent action of the individual arms is not required, simultaneous operation being effected as later described.

The pump 23 is secured to the front wall 25 having, as seen in FIGURE 2, only, a drive shaft 31. Referring to that figure, the drive shaft 31 extends through an inner wall 32 of the ring, a drive pulley 33 being secured to the shaft. A V-belt 34 extends from the pulley 33 to a fixed pulley 35, herein after the static pulley, secured to the frame 11. Thus, when the ring 13 is rotated by the prime mover, the pump is driven at a much higher speed. It is seen that the drive pulley 33, the static pulley 35, and the belt 34, provide epieyclic drive means for the pump-the relative diameters of the drive pulley and the static pulley being such as to provide a required pump speed.

A solenoid of the solenoid valve 36 has a two wire electrical lead 37 connected to slip rings, not seen in FIGURE 3, and later described with reference to FIGURE 4. The valve has two outlet ports, a line 38 connects one port to a manifold 39 fro-m which a flexible line 39.1 runs to a port of the cylinder assembly 26, admission of supply air to which line causes the abrader arm to assume the broken outline position 14.1. A line 40 connects the second outlet port to a manifold 41, a flexible line 14.1 running to a port of the cylinder assembly, admission of supply air through the line 4.1 causing the piston rod 27 to retract and the abrader arm to assume the position 14. The valve has a position admitting supply air to the line 39.1 only, a position admitting air to the line 41.1 only, and a position at which air to both lines is cut off with pressure maintained in the linesexcept for linkage. It is clear that the abrader arm can be held in any required position between opened as at 14, and closed as at 14.1, by placing the solenoid control valve in the cut off position. Pairs of flexible lines as indicated at 39.2 and 41.2, the number of pairs being according to the number of cylinder assemblies and abrader arms, extend to each cylinder assembly each of which is as above described thus effecting simultaneous action of all of the abrader arms. The ring 13, which is hollow, is airtight and is used as an air reservoir, or receiver, indicated at 49. A supply line 43 extends from an inlet port 44 of the control valve to an outlet port 45 extending through the ring wall 25 thus supplying air to the valve 36 for operation as above described.

A centrifugal oil separator 46, shown in detail in FIGURES 6 and 7 and later described, is mounted on on the ring front wall 25, the separator having an axis 47 which is disposed generally radially.

An oil tank 48 is secured to the ring front wall, preferably in a recess for protection and for conservation of space. The tank is small, capacity of about three pints being adequate.

Description of FIGURE 5 An air intake line 55 extends from an air intake 56 to the rotary pump 23, being connected to an air intake port 23.1 of the pump. A one way valve 57 is inserted in this line, the valve being adapted to permit flow only in a direction indicated by arrows 57-A, that is to say from the inlet 56 to the pump 23. An outlet line designated generally 58 extends from an outlet port 23.2 of the pump to an inlet of the air receiver 49, and the supply line 43 extends from the outlet port 45 of the receiver to the inlet port 44 of the control valve as previously explained in reference to FIGURE 3. The valve 36 is a stock solenoid operated valve adapted to admit air under pressure from the supply line 43 to operate the abrader arms as previously explained. A return line 59 extends from a T 43.1 of the supply line 43 to a T 55.1 of the intake line, the T 55.1 being inserted between the one-way valve 57 and the pump intake 23.1.

A one-way valve 61 is inserted in the return line 59, the one-way valve, a standard fixture, being normally closed and adapted to open when air in the supply line 43 reaches a determinate pressure, suitably about lb./ in. Thus, upon the determinate pressure having been reached, the valve opens and air circulates from the pump 23 through the outlet line 58, the air receiver 49, the supply line 43, the return line 59, as indicated by an arrow 61-A, through that portion of the intake line 55 between the T 55.1 and the pump intake 23.1, thence to the pump. It is thus seen that when the air pressure exceeds the determined pressure air will circulate as described, and is available substantially at the predetermined pressure to operate the cylinder means. That is to say pressure at the solenoid valve 36 cannot materially exceed the predetermined pressure, and it is to be noted that, when the relief va ve 61 is open, the air circulating as aforesaid is doing no work-except to overcome frictionthus does not load the pump.

It has been explained that the pump 23 is driven by epicyclic means when the ring is rotating, consequently the double acting cylinder means would then operate as previously descirbed, and in the absence of a receiver, so long as the ring is rotating at a normal speed. Consequently, the barker would be operative without an air receiverprovided that the pump has adequate capacity. However, without a receiver no air is available to operate the cylinder means unless the ring is rotating. It is advantageous to be able to move the abrader arms when the ring is not rotating, hence by providing a receiver as described, when the ring is stopped the receiver acts a reservoir of supply air initially at the predetermined pressure above, and accordingly air is available to move the abrader arms until the supply is exhausted. When the ring is rotating, the receiver is of advantage in that a pump of relatively small capacity is adequate since, once pressure in the receiver has built up, it has only to replace the air used in moving the abrader arms.

The pump 23 is suitably a Lockheed-Warner 9.2 cubic foot rotary compressor obtainable from ordinary trade sources. Used with a receiver or reservoir as described, a pump of this capacity and type is suitable. Other pumps can be used, for instance a Roots-type blower, or a piston pump, to obtain equivalent results.

As is well known, such rotary pumps require oil sealing to maintain design pressure. The oil tank 48 is mounted on the rotating ring, consequently centrifugal force urges the oil from an outlet of the tank through the supply line 62 to the pump. In this way, adequate oil pressure is provided by centrifugal force and without a separate oil pump. Because of the oil seal, air in the supply line 58 contains a material quantity of oil and it is obviously undesirable that all of the oil in the supply line reach the receiver, valve, and cylinders. For this reason the oil separator 46 is provided, inserted in the outlet line 58 between the pump and the receiver. A part of the supply line designated 68 extending from the pump to an intake port 63 of the separator will contain oil wet air, while a part of the supply line 58 as designated 69 extending from the separator to the receiver will contain air from which much, but not all, of the oil has been removed. It is desirable to have some oil or oil vapour in the line 69, so as to provide lubrication for the valve, and for the cylinder means, thus avoiding provision of separate lubrication for these units. As is later described in detail, the oil separator uses centrifugal force to separate oil from the oil wet air in the line 68. The axis 47 of the oil separator is generally radial, a separated oil outlet port being at a radially outer end of the axis.

An oil return line 65 extends from the separated oil outlet port, 66, of the oil separator to an oil return intake port 67 of the oil tank 48, separated oil flowing through the oil return line 65 to the tank 48. The oil tank has a capped filler opening 48.1 in the bottom wall facing the ring opening, thus centrifugal oil pressure does not act against the cap.

Description of FIGURES 6 and 7, the centrifugal oil separator The oil separator 46 is a hollow structure having a dome 72 and a base 73 disposed radially inwards as before stated, with the axis 47 generally radial. An extension of the line portion 69 is designated 74, extends within the dome, radially outwards from the base, to an open end 75, which open end is well above the base, suitably about a half of the radial heigth of the dome. The air line portion 68, being wet air intake, extends through the hollow dome to an open end 77 cut obliquely as shown, so that oil wet air entering in a direction indicated by an arrow 68-A discharges impinging tangentially against an inner wall 72.1 of the hollow dome 72. The oil wet air discharges as shown by broken arrows 78 impinging generally tangentially against the inner Wall 72.1. Because of the tangential impingment, and because of centrifugal force, a spiral motion will be imparted particularly to droplets of oil in the oil wet air. Since oil droplets, and smaller oil particles contained in oil vapour, are much heavier than air, these heavier portions will be urged by centrifugal force to an inner apex 79 of the dome to discharge through the oil return line 65 as indicated by an arrow 65-A. Air will enter the opening 75 as indicated by arrows 75-A, and discharge through the line 69, oil will thus have been removed from the air discharging through the line 69. The spiral motion of the air has cooling effect.

The opening 75 is above the point of entry of the line 68 to avoid direct or nearly direct exposure to the oil wet entering air. The opening 75, if close to the inner apex 79, can pick up an undesirable amount of oil. In practice it is found that disposition of the opening about half way between the base and the apex is satisfactory, however the position is not critical. Good results are obtained with this distance from one third to two thirds the radial height of the dome. As before stated, the point of entry of the pipe 68 is between the opening 75 and the base. It will be understood that when the ring is stopped there will be oil within the dome, and as explained provision is made for air stored in the receiver to operate the abrader arms when the ring is stationary. With the open end 75 disposed as above described, the possibility of separated oil entering the line 64 is reduced. The point of entry of the line 68 is to be well separated from the open end 75 for reasons above explained, and is preferably located adjacent the base 73.

The axis 47 is radial for reasons which will be apparent to those skilled in the art, but departures from that position can be tolerated. If the axis is not radial to an extent that the oil outlet port 66 is not at a greatest radial distance from the center of rotation of the ring, then oil will tend to collect in a part of the dome at a greater distance from the centre. This will result in an oil pocket which will remain until sufl'lcient oil is collected to discharge through the port 66. Of itself this may do no serious harm, but it is undesirable for avoidable excess of oil in liquid form to be trapped in the dome. By stating that the axis is generally radial, it is herein meant that the axis is so nearly radial that undesirable excess oil is not so trapped.

Description of FIGURE 4 In FIGURE 4, the belt groove of the outer periphery of the ring 13 is designated 13.1, and the static ring is shown by the reference numeral 35, being secured to the fixed frame 11 as shown. As before explained, the pump 23 is, when the ring is rotating, driven by the belt 34 engaging the static ring 35 and the pulley 33.

The slip rings previously referred to are here shown as designated 81 and 82, being secured to the static pulley 35. The slip ring 81 is electrically connected to a solenoid winding of the control valve, that is to say the control valve 36 of FIGURES 3 and 5, so that the valve moves to the abrader arm open position when the slip ring 81 is energized. The slip ring 82 similarly controls movement of the solenoid valve to cause the abrader arms to move towards the closed position. Sliding contacts, or brushes, 83 and 84, fixed to a part of the ring 13 are in electrical contact with the slip rings 81 and 82 respectively, lines 83.1 and 84.1 extending to terminals of a SPDT switch, a line 86 from a terminal of which is connected to a DC source 87 which is grounded as seen at 88. With the switch arm in the full line position shown the solenoid is thus energized to close the abrader arms, and with the switch arm in a broken line position the solenoid is energized to open the abrader arms. S-l is a three position, center off, spring return, switch. The solenoid valve itself is constructed and arranged so that when a winding of the solenoid is not energized, spring means urge the valve to a closed position at which as before explained, both manifolds 39 and 41 (FIGURE 3) are closed with supply air admitted to neither. Thus, when the arm of the switch 8-1 is moved to either position and released, the arm will return to an off or neutral position at which the abrader arms will remain held in a fixed position. As before stated, the solenoid valve used is a stock item, as are the electrical control means. In some solenoid valves, control is provided for instance by diode means, such means giving an electrical circuit equivalent to that described above.

Alternative configurations of the one-way valve 61 related to FIGURES 4 and 5 The one-way control valve 61 is constructed and arranged to open at a determinate pressure, accomplished by obvious spring means in known valves of this kind. One type of valve is adapted to open at a particular unadjustable fixed pressure, being the determinate pressure aforesaid. Other commonly available types having for instance knurled wheel means 91, FIGURE 5, for adjusting the spring tension so as to provide a range of pressures at which the valve will open. It is preferred that the valve 61 be so adjustable rather than fixed.

When such a valve is used adjustment is effected while the ring is stationary, this can involve difficulties. Accordingly, in an alternative adjustable embodiment a reversible DC motor 92 is provided, suitably a motor such as is in common use for winding windows in automotive vehicles, or an equivalent gearmotor. An output shaft of such motor is directly connected to the adjusting means 91, so that the opening pressure may be increased or decreased by means of the reversing motor. Electrical leads 92.1 extend from the motor to a second set of slip rings, see now FIGURE 4, designated 94 and 95 respectively and there shown fragmented. Brushes, not shown, are in contact with these slip rings, as before described with reference to the slip rings 81 and 82, with leads 94.1, 95.1, extending to 8-2, a DPDT centre oft" spring return switch, obviously connected to reverse the motor. In this way, the opening pressure can be adjusted when the ring is turning such adjustment being affected by the switch S-2 which is spring returned to a normal position upon release. This alterantive rapidly effects adjustment to particular conditions encountered without stopping the barker.

The circuit associated with S1 as shown in FIGURE 4 envisages a control valve having two solenoids windings with a common ground, or a single centre tapped winding with the tap grounded. An AC source could then be used were it advantageous to do so. With a valve having a single untapped solenoid, DC is used, with polarity reversing means such as for example, S2when a ground connection would not be required. Solid state polarity reversing means could be used. The particular solenoid means and circuit, and the particular motor and means of reversal thereof, are unimportant to the invention. Any convenient means of effecting remote control of the solenoid control valve, or remote adjustment of opening pressure of the one way relief valve, may be employed.

I claim:

1. A mechanical rotatably supported ring barker including; an abrader arm for removing bark from logs, pneumatic cylinder means actuating the arm, pneumatic rotary pump means operatively connected to the pneumatic cylinder means for supplying compressed air thereto, an oil tank supplying lubricating oil to said pump for maintaining a pneumatic seal therein, means for separating undesirable oil content from the compressed air, whereby the cylinder means are lubricated but not impeded; the arm, cylinder, pump, oil separation means and tank, being secured to, and rotating with, the ring barker; and pressure control means including;

(a) an inlet line from air intake to the pump, a one way valve adapted for flow of air through the inlet line only from the intake to the pump,

(b) an outlet line extending from the pump to a control valve admitting air under pressure to the cylinder means, a return line extending from the supply line and joining the inlet line between the pump and the one way valve, a normally closed one way relief valve in the return line, the relief valve opening at a determinate pressure so that, when the determinate pressure is exceeded, air circulates from the pump through the outlet line, the return line, and the inlet line, to the pump.

2. Structure as defined in claim 1, and having (c) an air receiver or reservoir in the outlet line between the pump and the return line.

3. Structure as defined in claim 2, and

(d) the oil tank having an oil supply line extending to the pump, said separation means including a centrifugal oil separator connected to said outlet line,

(e) an oil return line extending from a separated oil outlet port of the oil separator, to an oil return intake port of the oil tank.

4. Structure as defined in claim 3, the ring having spaced end walls defining a hollow structure with a central opening for passage of a log to be debarked, the hollow structure being adapted to form the air receiver or reservoir aforesaid.

5. Structure as defined in claim 4, the oil separator being hollow having an axis, a dome, and a base; the axis being generally radial with an apex of the dome radially outwards, the air inlet port being adjacent the base, the air outlet port being at an open end of an extension of the outlet line through the base, the separated oil outlet port being at an apex of the dome.

6. Structure as defined in claim 5, wherein the air inlet port includes means for tangential discharge impinging an inner wall of the dome adjacent the base.

7. Structure as defined in claim 6, the air outlet being disposed at a distance from the base of between one third and two thirds of the radial height of the dome.

8. Structure as defined in claim 1 and epicyclic means driving the pump.

9. Structure as defined in claim 5, and epicyclic means driving the pump.

10. Structure as defined in claim 1, and remote controlled solenoid means to operate the control valve.

11. Structure as defined in claim 5, and remote controlled solenoid means to operate the control valve.

12. Structure as defined in claim 9, and remote controlled solenoid means to operate the control valve.

13. Structure as defined in claim 1 and remote means to adjust the determinate pressure at which the normally closed relief valve opens.

14. Structure as defined in claim 12, and remote means to adjust the determinate pressure at which the normally closed relief valve opens.

15. Structure as defined in claim 13, the adjustment means including electric motor means effecting adjustment without stopping the barker.

16. Structure as defined in claim 14, the adjustment means including electric motor means effecting adjustment without stopping the barker.

References Cited UNITED STATES PATENTS 3,137,329 6/1964 Smith 144-208 3,333,615 8/1967 Robbins l44208 3,361,168 1/1968 Brown 144-208 ANDREW R. JUHASZ, Primary Examiner G. WEIDENFELD, Assistant Examiner

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