DE2331028A1 - VALVE FOR COMPRESSED AIR DRIVEN MOTORS, IN PARTICULAR FOR TOOLS FOR DRIVING FASTENING EQUIPMENT - Google Patents

Description

DIPL..ING. H. LSlN WEBER cipl-ing. H. ZIMMERMANN DIPL.ING. A. Gf. v. WENGERSKY

T.l.-Adr. Uinpat MVmImii T.Lfon (ItII) SMSf t9

Pottsdtadc account: MOndwn 22045

June 18, 1973 Z / Va / C

SIGNODE COßPOKATION, Glenview, Illinois, USA

Valve for -CHrt engines, especially for tools for driving in fasteners

The invention relates to a valve in a pressurized fluid-driven An engine in which a piston is reciprocated in a cylinder under the action of pressurized fluid. In particular the invention relates to an improved valve for such an engine and an improved pneumatically operated one Fastener driving tool using an air motor.

From pressure. fluid motor driven tools of various Type, including pneumatic, compressed air powered tools, are widely used in the art · To simplify the In the following description, reference is made only to the pneumatic version, it being noted that the invention is the same Way can be used with fluids other than air. A particularly useful embodiment of such tools is for driving in fasteners such as staples, T-nails and the like in relatively easily IU penetrating material

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is used, an example of which is described in US Pat. No. 3,106,131.

Although such tools are very satisfactory, they do not utilize the stored memory that drives the tool Fluid or air pressure with maximum efficiency. It was found that the pressure of the den The air driving the piston of the air motor is less than that of the compressed air before it enters the cylinder. This is mainly due to the relative slowness with which even people who work relatively quickly Conventional valves that supply compressed air to the cylinder.

The gradient of the valve opening must be reduced significantly before an optimal pressure transfer occurs the piston and an improvement in performance can be achieved can. A fastener driving tool with such advantages would result in an increase in the Working speed and the driving force acting on the staple, nail or other fastening means distinguish.

The invention provides a novel snap valve for controlling the flow of pressurized fluid into a chamber, particularly one containing a fluid motor. The valve comprises a valve support which is movably arranged next to a singang in the chamber and has a first surface for closing the chamber and forms an area outside the chamber which is exposed to the pressurized fluid. The valve carrier also has a second surface which is opposite the first surface. The area of the first surface is subjected to a first force due to fluid pressure which tends to bias the first surface away from the entrance. The second surface becomes one

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second force counteracting the first clamping force subject to clamp the component to the entrance. This second clamping force can also be applied to the second Area of acting fluid pressure are effected.

Das'Ventil also has a flexible disc, attached to the first support surface within at least a portion of the disc periphery, the disc is movable relative to the first support surface. The carrier presses the pane into the sealing system against the chamber entrance, while the second tensioning force counteracts the first tensioning force. When the first tension subsides, begins the wearer move away from the chamber entrance. Simultaneously the disk initially remains under the influence of the pressurized fluid that is then between the disk and the first The surface of the valve carrier flows into the sealing system at the chamber entrance. The fluid pressure pushes against the periphery of the disc the chamber entrance, although an inner portion of the disc moves up with the valve carrier. If the The valve carrier finally reaches a position at a certain distance from the chamber entrance, the disk jumps from the "entrance off against the first face of the support, whereby suddenly released a large opening in the chamber entrance to allow the pressurized fluid access to the chamber without pressure loss that normally occurs when the Fluid under control by a conventional one! Valve enters the chamber, initially only a small one ι releases the opening for the pressure fluid. Thus, the full available air pressure is used by the fluid motor, whereby due to the maintained fluid pressure e jhe substantial increase in the operating speed for a given fluid pressure as well as a substantial increase in the Energy and efficiency is achieved.

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Further details, advantages and features of the invention emerge from the following description. on the drawing illustrates the invention, for example, namely show: ■

1 shows a side view of a tool for driving of fasteners with a compressed air motor and one shown in section improved snap valve,

2 shows a partial view of the valve and the motor according to FIG. 1 with the valve opening and

3 shows the partial view according to FIG. 2 with the valve open and the piston of the engine in the driven position Position.

Fig. 1 shows a tool 10 for driving Fastening means with a compressed air motor 15, the a cylinder 20 and a piston 25 slidably disposed in the cylinder. A new type of snap valve 30 is used to control the motor 15. Although the Invention in connection with an improved tool for fasteners, the engine and valve can have many other uses to serve; the tool described is also exemplary of other tools in which the invention is also used can be.

The tool 10 for driving fasteners comprises a hollow housing 11 with a grippable elongated chamber defining portion 12, which is fastened at one end to a base plate 13. The housing section 12 defines a storage chamber 9. Furthermore, the housing 11 has on its other

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End of an upwardly projecting, substantially cylindrical portion 14, which consists of a at its lower end closed with the exception of a central passage 44: lower section / and a cap 43 for closing of the upper end of the section 42 consists. The storage chamber 9 can contain compressed air and is connected to the Base plate 13 adjacent end via a hose and connecting parts 16 with a suitable source of such Air connected.

The engine cylinder 20 is open at its ends! a smaller diameter than the housing section 14, in which it is centrally located so that an annular chamber 17 between the outer wall of the cylinder 20 and the Inner wall of the housing section 14 is formed. The lower end 22 of the cylinder 20 is closed by the the lower end of the housing section 42, with the exception of the passage 44, is closed. The annular chamber 17 is filled with compressed air, since it is in direct connection with the storage chamber 9. The cylinder 20 has one Height that its upper end 21 is just below the upper end of the housing section 42 after installation. Of the Housing section 42 is provided with a flange which has an annular palm adjoining the cylinder end 21 45 forms.

The piston 25 is slidably mounted in the cylinder 20. It has an upper end 26 and a lower end 27 and is displaceable between the cylinder ends 21 and 22. The piston 25 can be by any suitable means, for example a spring can be biased upwards towards the end 21. Preferably, the piston 25 and the Cylinder 20 built so that they have a chamber between them; 61 extending from the chamber 17 via passages 46 is charged with compressed air in the cylinder v20. The free-

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Lowing area of the upper end 26 of the piston in the Kan.mer ^: 61 is greater than that of the lower end 27 of the piston in ι the chamber 61, which results in a balanced upward force. The further details of one such

Piston pretensioning devices are known from US Pat. No. 3,106,131 mentioned at the beginning. The piston 25 is through the compressed air from the chamber 17 against its clamping force downwards moved towards the cylinder end 22. He is also with ι an axial passage extending between its ends 24 for venting this air through passage 44 upon completion of the descent cycle is provided with it

'The piston is returned to its upper position by the piston tension Position can be brought.

At the lower end 27 of the piston is a driving device 39 attached for staple, which extends vertically through the central passage 44 and an i'ünrun ^ 40, which is part of a staple magazine 41 attached to the Base plate 13 is attached under the cylinder 20 and the section 12 on one side thereof. Be in the Lagazin 41 Staples in a row across the path of the drive mechanism 39 and delivered one after the other under the driving device 39 into the guide 40 in order to be fed in when sica the piston 25 with the driving device 39 downwards towards the lower end 22 of the cylinder 20 emotional. The details of such a tool; for driving fasteners are from the above mentioned US-FS 3,106,131 known.

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. For periodic supply of compressed air to drive the piston 2 ^ is still down at the top of the cylinder

the novel snap valve 30 is provided. Unlike known valve designs, the valve 30 opens fully once in a completely new way of opening.

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snap, which momentarily creates a large opening at the cylinder end 21, so that the compressed air enters the cylinder without pressure and consequently without loss of drive energy and performance of the piston, which would be inevitable without the new type of valve. The valve is carried by the cylindrical section 14 of the housing and has a thin circular membrane 31 which has a diameter which is at least as large as that of the surface 45 of the cylindrical housing section 42. The membrane is provided with a rigid circular support plate 32 on one side. A resilient, flexible circular disk 33 with a diameter which is equal to or preferably slightly larger than the outer diameter of the cylinder 20 is arranged on the other side of the membrane 31. The disk 33 is preferably! made of plastic material, although other resilient materials can also be used. This component is extremely important for the "snapping" of the valve to instantaneously; to create a large opening at the end of the cylinder. In particular, the disk is used to audition the cylinder end 21 as the membrane 31 begins to move away from the hand 21 until it finally "scans away" to reveal a large opening, as will be described in detail later. The plate 32 and the washer 33 are both fastened to the membrane by a screw nut-bolt unit 35, the bolt of which passes through the two parts in the middle. In this way the periphery of the disc 33 is not itself connected to the membrane 31, a fact which is important for the "snap ^{11 of} the disc 33, as will be described later".

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Neither the cylinder 20 with the piston 35 nor the valve 30 must necessarily be round; instead, the cylinder, for example, can just as well a tubular component with a square or rectangular Be cross-section and the valve 30 with the disc 33 has the same square or rectangular cross-section exhibit. Furthermore, it is not necessary either in the round or in the square design that the disc in the Middle is attached to the membrane 31, as long as it is only within at least part of the disc circumference attached and moved relative to the membrane v / ground.

The valve 30 is flanged over the palm 45 of the Arranged at the end of the section 42, the disc overlapping the '.ende 21 and sitting on it. In this position lies an outer, essentially ring-shaped section 36 of the i-membrane 31 above the outer surface 45. The open End of the cap 43 is also flanged and forms a second matching annular surface 46 which is in correspondence be attached to the surface 45 on this can. The valve 30 is made by clamping the annular diaphragm portion 36 between the cap 43 and the housing portion 42 firmly connected to the housing section 14, the corresponding bands and the annular section coincide with their centers.

When the valve is properly positioned in this way over the top 21 of the cylinder and in the housing section 42 is attached, it separates the annular chamber 17 from an upper chamber 18 within the cap 43 and above the plate 32. An annular intermediate section 47 of the membrane 31 bridges the annular chamber 17 between the cylinder 20 and the housing section 14 and

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is provided with an annular, upwardly bulged, convex bulge 37, around the lying above the cylinder 20 Portion of the diaphragm to move upwardly away from end 21 from its normal first position at the cylinder end 21 to move into a second position lying at a distance from this, as shown in FIG.

The membrane 31 can also be replaced by another movable valve support part, for example a piston or a rigid plate, which is slidably and sealingly fastened in the housing section 14 and, in a similar manner, a chamber like the upper chamber 18 above such a movable one support member and an annular chamber as the \ chamber 17 can create under it, as well as this component between a position at the end of 2Λ would be in the Membraji 31 in a movable distance from this lying position. The resilient washer 33 would similarly be attached to a surface of the component in order to seal the cylinder at its upper end 21.

A downward biasing force must be provided to the valve 30 to the cylinder 20 and to press the disk 33 in the sealing position against the cylinder end 21 (preload) so that the cylinder 20 against the compressed air is properly sealed until the moment the piston 25 is to be driven. One such biasing force can be achieved by using different Einricntungen, such as a spring and a release mechanism are generated, which are from above on the support plate 32 act, or by creating a difference between the areas of the upper and the lower membrane surface exposed to compressed air. Preferably, however, the downward biasing force is citels des of the storage chamber 9 via a control valve 50 and a line 28 supplied to the chamber 18 air j

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pressure generated in cooperation with a relatively light compression spring 19 in the chamber 18 in order to ensure that that after driving the .Eintreibeeinrichtung 39 and the

! Introducing high pressure air into chamber 16 through valve 30

returns in the sealing system at the end of the cylinder 21. The administration 28 is in part of the wall of both the cap 43 and

j also installed in the housing section 42 and extends

are essentially vertical to the housing section 12. An

j »

j its upper end opens the line into the chamber 18, while at its lower end it opens into the control valve 50 which is adjacent to the lower surface of the housing section 12 is attached to the cylindrical housing section 14.

The control valve 50 has a central control chamber 51 into which the line 28 opens with its lower opening 52 and in which a ball 53 is arranged. The valve ': has furthermore an inlet opening 54 and an outlet port, the SiCN substantially vertically above or below the control chamber 51 extend, the inlet opening 54 and the outlet port 55 communicates with the storage chamber 9 to the outside atmosphere. A Auslösehei_el 57 actuates a valve tappet 56 resting with one end of the ball 53 in order to move the ball from a first position in which. ie leaves open the outlet port seal, and whether the inlet opening 54 to move vertically into a second position in which it seals the inlet port 54 and outlet port 55 can be open.

Normally, the ball 53 rests in the lower part of the chamber 51 in the first position. This is the position in which the upper chamber 18 via the line 28 and the valve 50 with the storage chamber 9 in connection and is therefore with Lruczluft supplied. As will be recalled, the annular lower chamber 17 is in constant communication with the storage chamber 9

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is constantly sent with this reply. Thus, the compressed air strikes the upper and lower surfaces of the valve 30 in both the upper and lower chambers 18 and 17, with opposing forces being built up and down on the valve. The air in the upper chamber 18 acts on the entire upper surface of the valve, while the air in the lower chamber 17 only acts on the annular intermediate section 47 of the diaphragm 30, since this is the only part of the lower surface of the valve which is the compressed air in the chamber 17 exposed i: t. The air pressure prevailing in the chamber 18 thus acts on a much larger area than the pressure prevailing in the chamber 17, whereby a large downward force is generated vdrd, which the valve 30 in sealing system with the. inde top 21 to the cylinder 20 pushes down on the cylinder 20 and the biasing plate 33 and thus the cylinder 20 is isolated from the chamber 17 ^ This is the ones shown, in FIG. ^1; divided position of valve 30.

A force acting below could also be achieved without a difference in difference in favor of the upper valve surface ^; if the chamber 18 is simply loaded with a correspondingly higher -LUitaruck or, as mentioned above, a relatively strong spring and release mechanism is provided.

The tool can then be put into operation by moving the release lever 57 upwards, whereby the valve piston is driven and the ball 53 is moved upwards, u :: i preferably only momentarily to close the inlet opening 54 and to open the outlet opening 55, whereby the air from ^: the chamber 16 via the line 28 and the outlet opening 55 is directed to the outside into the atmosphere. When the air pressure in the chamber 18 decreases, the force acting on the annular intermediate section 47 of the membrane becomes essentially equal to the force due to the air pressure prevailing in the chamber 17.

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pressure exerted force which presses the membrane 31 upwards into its lifted position. Although such a decrease in air pressure appears to occur momentarily in chamber 18 as far as it relates to the work of the tool, it has a finite time gradient a, which allows air pressure in the chamber 17 to be between the Disc 33 and the diaphragm 31 act around the circumference of the disk 33 to press down in the sealing system on the cylinder end 21, even if the membrane 31 is upwards is moved into its lifted position. In this way, the opening of the cylinder 20 for the compressed air is delayed, until the diaphragm (or another valve support component) moves up into its second lifted position has arrived.

Before the connection between the disk 33 and the cylinder 20 is finally interrupted, has the remaining part of the valve has time to move away from cylinder 20 to solve, so that α & ε opening of the cylinder for the compressed air, when it finally happens, vigorously i .-. t. just as important it is that ds ε open by snapping off the disk vcm Cylinder 20 away into a position in which it rests flat on the membrane 31, momentarily takes place, as later nocrx is described. Such a process can only be achieved if the manner of attachment of the disc 33 not only allows them to move relative to the membrane can, but that at least most of the circumference of the disc is not attached, so that the air pressure in the chamber 17 this circumference against the cylinder hand presses. The reason it is nctv / endig, the disc within at least part of its circumference, preferably to fasten it in the middle should now be clear.

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The state of the valve shortly before the moment at which it opens is shown in FIG. even when the circumference of the disk is pressed down against the cylinder linden 21. The disk is thereby deformed convexly or conically, as shown in Fig. 2. Due to the elasticity of the disk, with increasing deformation within the disk, a restoring force is built up which the disk wants to return to its normal flat shape 4 When the air pressure in the chamber 18 finally equals the atmospheric pressure and the membrane reaches its second position at a distance from the cylinder end 21 under the influence of the air pressure in the chamber 17, the restoring force overcomes the resilience of the Disk is the force of the air pressure acting downward on the circumference of the disk. The disk snaps away from the cylinder into its original flat position Position on the lower surface of the membrane 31 (see ng. 3), which is in its second position away from the cylinder 20. A large circular opening between the cylinder 20 and the pressurized chamber 17 is \ create currently Ge, which allows the high-pressure air in the chamber 17; to flow into the cylinder 20 essentially with a minimal pressure drop. The air impinging on the upper surface of the piston 25 overcomes the upward tension of the piston causing it, together with the driver 39 and the associated staple delivered from the magazine 41 to the guide immediately below, to be momentarily pushed downward.

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Meanwhile, when the release lever 57 with its ünde is pushed up, the valve piston 5ö and the ball 53 can return to their starting position, v / uei the ball 53 closes the outlet port 55 and opens the inlet port 54, whereupon the toggle trigger returns to its original position Location in front of the. Readout by the operator returns. When the inlet opening 54 is opened, compressed air flows again from the storage chamber 9 through the opening 52 and the line 28 in the upper chamber 18 so that together with the compression spring 19 has a downward force on the valve. The resulting downward-looking Force pushes the membrane 31 into its former position near the cylinder first position, while the disk 33 is brought into sealing contact with the cylinder end 21, to the compressed air cut off from cylinder 20, it should be noted here that any other control valve and pipe arrangement, which also optionally promotes compressed air to the upper chamber 18, as well as it discharges from there on Befenl, likewise the would fulfill any intended purpose and that the control valve 50 and the line 28 are only described as an example.

The pressurized air in the cylinder passes through the axial passage 24 in the piston 25 and passage 44 at the bottom End of the housing section 42 from. A wide variety of others Alternatively, means for letting out this air are available, since the valve 30 also acts on the piston 25 the full air pressure in the chamber 17 works so quickly that the loss of drive energy through such an air outlet device is negligible. As soon as the cylinder 20 is closed again by the valve 30, the Piston 25 returned to its normal upper position at the cylinder end 21, as described above, to the next Wait for the tool's drive cycle.

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The improved valve for the fluid motor achieves a substantial increase in the efficiency, the driving force and the working speed at any working air pressure compared to known devices. This is the case because the cylinder genη the air pressure ^; zurr. Drive of the piston is sealed, also when some components of the valve begin to move away from the cylinder until the sealing washer can suddenly snap away from the cylinder and into a position remote from it; .m. * vuf ^r . ^; In this way a great opening for the one becomes tr ·, i ^ ;. ..er Drue ". air released into the cylinder momentarily, wecuro '.. ier r.axiir.sl available air pressure with a minimum ^

loss of the existing air pressure is applied to the piston. The air consumption of devices with a hot-run tool is reduced and their lnerrric ...- is increased, the devices being driven in more vigorously with improved scaling effect. As if:. ", Hew / i / nt, j can be the improved a i-lotor and inventive OÄ.: Ε ·; e:, ~ ile at ^ edei :: any similar V / Erkseug b: .vf. In any. Field of application ., in which a solcner requires ilotör wiii used weröen The invention is AUCR: not ad, le working application fields limited with L__teuert- _L, they also άε j κιt änderen Strömun ^ snitteln verv; c-adet can be;.

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Claims (1)

- ie - latent claims: e: © Kit snap action · working valve sum It Controlling the flow of fluid under Lruci into a chamber, identified by one on Lruckdii'ferenz appealing valve support (31) and by one attached to the valve support (31) within the circumference of the chamber (61), when the valve (31) is in the raised position of the chamber (31) and is located in the sealing system on the chamber (61) and to momentarily open a large inlet port. into the chamber through which the fluid flows with minimal pressure loss flows into the chamber (61), from this resilient disk (33) snapping away. 2. Valve according to claim 1, characterized in that that the disc (33) is fastened in the middle on the first surface of the valve support (31). 3. Valve according to ^ nsprucii 1, characterized in that that the valve support (31) is an elastic liei / ibran, which is held in the vicinity of the combing entrance (21) on its circumference. 4. Valve according to claim 1, characterized in that the valve carrier (31) has a first surface for closing the chamber (61) which forms an area (47) outside the chamber which is exposed to the pressurized fluid. and a second surface facing opposite to the first surface defining an area exposed to fluid pressure which is greater than the exposed area (47) of the first surface, and in that the fluid pressure acting on the exposed areas is a pressure exerted on the valve (30). causes usable preload force acting in the seal on the K ₅ mine inlet (21). _ ₁₇ 309884/0454 b. Valve according to claim 4, characterized in that the valve carrier (31) overlaps both the chamber inlet (21) and the disc (33) and that the exposed area (47) of the first surface lies outside the chamber (61) and in is formed essentially ring-shaped. 6. valve for controlling the flow of under pressure employing; Fluid to a fluid motor, which is in a :, tubular Component is housed, characterized by an at the open end (21) of the tubular component (20) arranged valve support (31) with a first surface to close de.ses end (21), one outside of this Lndes exposed to fluid under pressure Area (47) forms, and with a second surface facing opposite to the first surface, wherein the first surface is subjected to a first tensioning force caused by the pressure fluid, the first surface from the circular Component (20) pushes away, 'while the second surface is subjected to a second tensioning force counteracting the first force, and also by a second tensioning force on the first surface of the Valve carrier (31) within at least a part of its circumferential fixed resilient disc (33), which relative to the first support surface is movable and the valve support (31) due to the second clamping force in ^ sealing system can be pressed against the i.nd (21) of the tubular component (-20) is, and by a device (50) for .trigger at least a portion of the second tension for effecting a Movement of the valve carrier (31) by the pressurized fluid away from the end (21) of the tubular member during the initial Maintaining the sealing system of the resilient washer -16- 309884/0454 2331-28 -loan this end (21), which finally snaps away from the tubular component (20) from the other (21) when there is enough of the valve support and a large opening _L in the inde (21) of the tubular component (20) to the uinlai des vrwj iluids Drive of the fluid motor releases momentarily. 7. Valve according to 6, with a housing which integrates the fluid motor and the valve 5, marked by the fact that the valve (50) is cracnt on an inner wall of the housing (11) and the housing is in a first chamber (10) on the side of the second surface of the valve and a second chamber (17) surrounding the tubular component (20) divides on the side of the first surface of the valve, which can be continuously supplied with pressure fluid to generate the first clamping force is. 309884 / CH54