JPS5894976A - Air operation power tool for clamping screw connecting section - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pneumatic crab tool for tightening threaded connections. In particular, the present invention includes a housing, a first motor for obtaining an initial tightening degree on the threaded connection, a second motor for obtaining a desired final tightening wrinkle on the threaded connection, and a power source for the motor. The present invention relates to a threaded connection tightening tool of the type comprising a power transmission system for transmitting power to an output spindle connectable to the connection.

A kernel seed tool is described in US Pat.

The problem with this traditional moving crab tool is that it consumes a lot of air. Both motors of the same tool are supplied with compressed air simultaneously during the entire tightening process. This means that the second motor, which always operates in a lower gear than the first motor in order to achieve the final tightening of the threaded connection, runs unloaded during the initial stages of the process. Such idling of the first motor wastes a considerable amount of compressed air, and in addition to undesirably high energy costs, it is difficult to convert the more common single-motor tools of the impact or stop type to the more rapid-acting tools. Converting Fi, very expensive measures may result in having to make the compressor unit and air distribution network large.

In view of the high level of air consumption that today's motorized tools undergo, it would be extremely difficult to adapt these tools to the details of portable tools, first of all the required air supply and exhaust. The conduit is not flexible enough and lightweight enough to allow satisfactory throat handling of the tool! Ninth V
The air passage extending into the tool housing containing the Cx throttle valve must be sized such that the tool housing dimensions and stacking permit as a portable tool.

The main object of the present invention is to provide a pneumatically actuated commuter screw connection tightening device in which the consumption of compressed air is effectively reduced. According to the invention, a reduction in air consumption of up to 10% can be achieved.6 Another object of the invention is to control the supply of working air to the low-speed high-torque motor by reducing the counter-pressure from the high-speed, low-torque motor. An object of the present invention is to provide an air-operated two-motor nut-turning tool with a compressed air supply valve arranged to operate at a constant difference between the air pressure and the actual air source pressure.

Further objects and advantages will be apparent from the following description and claims.

Preferred embodiments of the invention will be described in detail below with reference to the accompanying drawings.

The movable crab tool shown at 81 is an air-operated nut runner 66 having a housing io, in which a first motor // and a λ-th motor are held. The inner motor is of the air sliding vane type, which is the type of motor periodically used in this type of machine. The motor is of inappropriate dimensions as shown in Figure 5.
o It also rotates in the opposite direction.

The tool shown is a portable tool.
A pistol-shaped grip J)/J is formed.

The main air supply passage l# of the tool extends therein. Throttle valve l that can be installed with pistol type grip Btiyc! trigger 1 to control the flow of compressed air through air supply passage l-
1.

Motor ii and here are the coupling device/I and reduction gear l? is arranged to transmit torque via the square-ended output spindle 17 (see figure 87).

The reduction gear comprises two conventional planetary gears, which are not shown in detail.

The coupling device has at its forward end a solid shaft Q formed -xt5 for engaging the reduction gear. Solid shaft-
20 is equipped with a spur gear 2 at its rear end, which meshes with a small spur gear 3 driven directly by the first motor ti. The small diameter spur gear J directly driven by the λ-th motor is the inner gear of the joint sleeve. meshes with The coupling sleeve is axially separated by a roller bearing core, 21, which connects the solid axis λO! lc is supported so that it can be rotated. These roller bearings λ7. An axial clutch 30 is disposed between the shafts t, and the threaded joint tightening with respect to the joint sleeve 24 is carried out in the direction of the solid shaft 20.
allows free rotation of.

Clutch 30 is a free rolling clutch of any conventional design and therefore will not be described in detail.

In the illustrated coupling 11, a reduction ratio between a spur gear 23 and a spur gear drivingly coupled to a reduction motor is shown.
The reduction ratio between male gear 2v and internal gear j, which is drive-coupled to the second motor, is approximately 7. ! :/ is. Thus, the deceleration of the first motor /J is approximately 3.7j times the deceleration of the first motor //. This coupling device tt#
It has an i-concept design and a fairly high-speed reduction ratio of the No. 1 motor/J rounding.

The λ motors 1/ and /J4C are provided with air populations J/ and 3J, respectively, through which the motors are connected to the supply valve 3.
Compressed air is supplied from 33. For this reason, supply valve J
JK- is provided with an air population/-) 77 that communicates with the housing lOO main air supply passage lhiro.

The air supply valve J3 comprises a cylinder bore II and a valve element JF slidingly guided therein. The valve element J is tip-shaped and has a circumference of its periphery and a number of air communication openings extending through its bottom or end. At the end of the valve element J, a central opening through which the rod #J extends is also provided.
J and valve element J are axially connected by a lock connector ##.

One end of the rod-J is guided into the tubular part #l to which the cylinder hole ivy and the coaxial KWII are attached on the left side of FIG. 1, and the receiver is stopped. The bottom end of tubular part-I communicates with the atmosphere via passage-4. 1stlFli seal O between the valve element Jde and the cylinder bore Jt.

3) and tubular section #j cooperate to prevent the compressed air supplied through the air outlet, JP-) 37, from leaking into the atmosphere through passage-6.

The μ rod #3 passes straight through the valve element JF and is also equipped with a vibration damper @ #r at its right hand end, this device has a brake piston 3, an 0 cylinder jO and a supporting cylinder si. are doing. These three mourning bands are prevented from moving in the axial direction by a single ring. The brake piston is fitted into the hole Jl with a circumferential distance S, but the rod is inserted into the hole J with a circle lI gap that is larger than the gap on the outer circumference.
K-uke can be stopped.

This means that air is passed through the gap by the brake piston and that the brake piston can move freely relative to the rod JK within very narrow axial limits of travel.

The valve elements If, -Tsudo Yume 3 and the brake device @#1 can be mutually displaced as a unit in the cylinder bore II between the final O-end positions, said positions being the positions of the tubular part -JO bottom- and the cylinder bore 3t, respectively. A weak coil spring sr, limited by the end of the rod≠3 striking the right hand @jJ, is arranged to bring the whole unit to the right of the figure and thus when the tool is started the valve element J? is always in its right-hand end position.

In addition to the air inlet /-) 77, the cylinder hole 3t has a seventh
The first service port (j4) communicating with the air port 31 of the motor 1 and the inlet 3-2 of the second motor 12
A Jth service part j7 is provided which is in communication with the service part j7. Air inlet bow as shown in Figures 2 and 3)
77 and the first service bow) j4ij they are valve element 3
2 is placed in the cylinder hole 1r so that it is never covered by the cylinder hole 1r. The second service port j7 is covered by the valve element JP when it occupies its right-hand position;
When the valve element J is displaced to its left hand position, it is not covered through the square.

The operating sequence of the apparatus shown in FIGS. 2 and 3 is as follows.

Before the valve 33 is supplied with compressed air and during the initial steps of the threaded connection tightening process, the valve element 39 occupies its right-hand position as shown in FIG. When no compressed air is supplied to the valve 33, the loading of the spring sj ensures that the valve element 3 occupies its right-hand position, ie the closed position Iikτ.

The tool is a throttle valve/! t-Initiated by pressing trigger/6 to release. Then the compressed air passes through the passage l≠
Tools are supplied via the bus.

During the initial steps of operation, compressed air enters the valve 3J via the inlet boat 37 and passes through the openings U/, (and also the first service 4-) of the valve element 3 and the first motor. The first motor // is reached via the air inlet 31 .

The Ixl motor //ifi rotates the solid shaft -20 through the spur gears 3 and 1, and the power generated by the first motor // is transmitted to the outlet spindle 17 through the reduction gear 19. Ru. During the process stop procedure, the resistance to rotation δi occurring in the tightened threaded connection is low, which means that the rotational speed of the first rotor 11 as well as the air intake through the supply valve 33 are high. do.

When compressed air passes through the opening 4cl of the valve element 32.

A pressure drop across these openings is created. The pressure on the right hand side of valve element 3 is the pressure on the opposite side.

This means that the pressure is lower than the pressure of the compressed air source to which the unloading tool is connected. However, in one opposite direction the valve hair $3
The difference in the loads acting on F is due to the fact that only a portion of the drawn cross-sectional area of the valve element 3, i.e. the surface area represented by the cross-section of the rod 3, is exposed to atmospheric pressure through the ventilation passage 6V. , is not as large as this pressure difference suggests. The rod 3 is exposed to the same pressure as the valve element at its opposite end.

The brake piston≠2 does not have any real influence due to the pressure acting on its right hand 11.

The different surface dimensions of the valve element 3 and the dimensions of the opening reference 1 are:
are selected in such a way that as the resistance of the threaded connection increases and the rotational speed of the first motor decreases to a certain range, a significant increase in the counter pressure from the motor is obtained. Ru. At a predetermined tightening rate of the threaded connection, the back pressure from the first motor ti is large enough to move the valve element JP to the left and occupy its open position, thus causing the valve tf4 to move to the left and occupy its open position.
11eυ is aligned with the second service port j7 (see Figure 3), the supply valve 3J is connected to the second motor/-2 without blocking the 1μ supply of air to the first motor/I.
A second motor, which provides compressed air to the first motor, is energized to perform the final tightening procedure in conjunction with the first motor. λth motor l
The output torque of KO is transmitted to the joint sleeve KO≦ via the spur gear KO and the internal gear KO.

The gear ratio of this internal gear-to-spur gear arrangement is greater than that of this spur-wheel arrangement connected to the first motor ii, because the coupling sleeve is rotated more slowly and is solid. Axis. All that means that it is turned over at a higher torque level than what it originally was. However, due to the increased resistance of the screw connection being tightened, tA/
The motor l/ is decelerated to a low speed level such that the motor lλ can catch up, and the one-way clutch 30 is also connected. The force of the motor λ is transferred to the solid shaft O and is added to the 1D force generated on the housing by the first motor Ik.

Once the desired final tightening ratio is achieved in the threaded connection, the total back pressure from both motors is compared to the preset air source pressure and responds as a fill valve or fill valve. By stopping as a result of the closure of the counterpressure, motors II and I stop rotating. The escape valve is not shown, but is of any conventional design and is located upstream of the supply valve 33.

The braking device is used to prevent valve hair lA3 from vibrating and to achieve accurate operation of supply valve J3.

Therefore, the brake pistonner is located on the right hand and in the cylinder hole II.
arranged to prevent air flow to a certain extent from or into the portion of the It is desirable that the valve element J has a small effective damping during its movement to the left with little interference with movement in the opposite direction.

The circumferential gap between 1m11+piston-2 and rod #3 establishes a second air passage through the brake piston wide. However, this passage is limited to the valve element 3.
It can only be fully opened when the brake piston 3 and the brake piston 2 are moved to the left. When moving to the right, the brake piston V is brought into contact with the O-ring SO, thus closing the second air passage and providing an even more effective braking action.

In Figure 1 a modified embodiment of the air supply valve is shown with reference numeral 13.
3. The purpose and main operating sequence are almost the same as the valves described above. Special features of the valve according to Figure 1! The second is a rod iui designed differently, which is a coaxial ventilation passage 1u
6 and which at its tenth end encloses the opening /10 of the cylinder end wall /13, thus on the one hand the tubular part l≠5
Communication is achieved between the chamber formed by the loft 1443 and the atmosphere externally. The head il/Id is guided in a sealed manner within the tubular section t4IS and is also provided with a ventilation passage lμ6.
This exposes the head to atmospheric pressure on its left end face. The head tri also has an annular shoulder/1 exposed to air source pressure.
form 2.

The manufacturing cost of the supply valve according to the embodiment shown in FIG. 1 is very similar to that of the valve shown in FIGS. 2 and 3.

This means that the valve element 13 is balanced between the air source pressure and the counterpressure from the first seventh tank.

In the embodiment of the present invention, the large difference between the pressure related forces acting in two opposite directions on the valve element is compensated for by having the left end face of the rod 4I-3 in communication with the atmosphere. while the right hand side is exposed to the counter pressure of the first motor.

In the valve shown in Figure 1, the right end face of rod/413 is actuated only by swivel pressure. The reduced force generated then and acting to load rod l#3 to the left is:
An annular shoulder 1129 is created by the acting air source pressure.

Apart from these differences, the principle of operation is the same as in the two embodiments of the valve. The valve element 13 of the valve shown in FIG. 1 is therefore biased to the closed position by the cover spring 1ssK towards its right. This means that the valve element 13 assumes its closed position before the tool is actuated in any way. However, when the initial stages of the pivoting process are started, the forces emanating from the pressure drop across the opening iui will dominate the biasing force generated by the spring iss. In this closed position, the first service in the cylinder hole iit/! 7 is covered by the valve element 13 and thus prevents the moving air from reaching the second motor lλ.

If the torque resistance from the tightened threaded connection increases to a certain level, the counter pressure from the first motor l/ will force the valve element 13 into its open position KN. At this position,
The valve opening /410 of the valve element 139 is aligned with the second service port 117 and compressed air is supplied to the second motor /λ. Air inlet port 1 in both positions of kV element 13
37 as well as the first service ID tzt are released.

The vibration damping device ilt of this embodiment is designed and operates similarly to the device of the embodiment described in hl.

Advantages of certain embodiments are independent of certain air source pressures. In other words, this valve also operates correctly when, for one or other reasons, the pressure of the supplied air deviates from the II car positive pressure, which is normally 6 nodal. A pressure drop of λ~3 pearls is not unusual at such a tool connection point.
However, the air supply valve mentioned above is balanced between the supply pressure and the counter pressure from the first motor, which means that the pressure pressure per se is not important. It should be noted that the biasing spring 22°/Ij is too weak to have any effect on valve operation.

When the koji layer shown in Fig. 1 is used, the reduction gear of the tool changes.

Tool housing 10ti by I-le bearing data
c It is shown enclosed within a casing holder O which is supported for rotation. A ball bearing forms a swivel connection between the housing io and the reduction gear casing ta.

Is there a torque reaction rod at the front end of the casing ta? The screws are tightened or tightened so that they come into firm contact with a fixed part, such as a protruding part of any of the parts which are fastened together by a screwed connection. The reason is that the torque reaction is too heavy to be counterbalanced by the tool operator.

The purpose of the universal connection is to quickly and satisfactorily adjust the recoil rod.
The aim is to provide a firm grip for the recoil bar without compromising the operator's ability to hold the pistol grip in a satisfactory position. /j Find the supporting point.

In conventional single motor tool applications, a flat, free rotating swivel connection is satisfactory because the reaction torque transmitted from the motor alone to the tool housing is low enough to be harmless to the operator. .

However, in the co-motor tool shown in FIG. This is achieved by applying internal gear drive to motor/J.

In order to protect the operator from the reaction torque generated by the housing ioK, a circumferential row notch notch 3 is provided on the casing holder 1, and these are hemispherical in shape. Equally distributed around the rear end of Q (
(See Figures 1 and 4).

There is a vertical surface hole between the casing P0 and the handle of the trigger/4! Ashi, there are λ steel balls on this6. 7 is movably guided. Hole! is the same as Notsuchita 3! It is arranged in the lI plane and makes it possible to engage the upper i-ruter 6 with one of the notchters 3.

A locking sleeve is slidably guided in the handle of the trigger, and a spring 100 is inserted into the opening of the trigger, and the trigger 1 is inserted into the opening of the trigger sleeve.
6 is arranged to generate a biased load in the direction of 6.

The lock sleeve is provided with a circumferential haze.

It is dimensioned and arranged to partially receive the lower I-ruter 7 when the trigger 16 assumes its rest position. This position is shown in Figure 1. i-ruta 6. The dimensions of the trigger 7 are adapted to the distance between the trigger handle and the casing ta, so that when the trigger 14 is pulled to start the engine JL, the g4yr is also bored! As the upper selter 6 is moved out of alignment with the notch holder 6, it engages one of the notch holders 3 of the casing holder O and is fixed. In other words, when the tool is operated, the casing data 0 is always fixed with respect to the tool housing lOK. This means that the total reaction force generated in the tool is balanced by the reaction rod λ.

When the trigger /6 occupies K's body position riIi as shown in Fig. 1, the lower ZELTA 7 enters the tile J.

Also, the upper ball 26 is removed from the notch 3 and allows rotation of the casing data O with respect to the housing 10. From yet another point of view, one of the Notsuchita 3 is above--Ruta 6
If properly aligned with hole Fj to receive the trigger l≦ cannot be moved. This means that the tool cannot be operated unless the housing 10 is fixed with respect to the reduction gear case nog Q and the reaction rod tacho.

It goes without saying that these embodiments are not limited to the above-mentioned examples and may be freely modified within the scope of the present invention.

[Brief explanation of the drawing]

FIG. 1 shows a partially cutaway side view of a portable power wrench having features of the present invention. FIG. 1 diagrammatically shows a movable crab device according to the invention, with the air supply valve shown in its closed position. FIG. 3 shows a fragmentary sectional view of the air supply valve in the open position IIK. FIG. V shows a longitudinal section through the air supply valve of a modified embodiment. 5M shows a cross-sectional view taken along line V-V in FIG. 1. FIG. 6 shows a fragmentary side view of the tool of FIG. 8I1. io...Housing, /l...First motor. /U... λth motor, /J... pistol-shaped grip, 17... output spindle, /r, /ri... power transmission system. 31.3λ...Air inlet, 33. /33・-Air supply valve 182 14/

Claims (1)

[Claims] 1. A first rounder (//) to achieve an initial percentage pretension in the threaded connection and a rounding pattern to achieve the desired final percentage O pretension in the threaded connection. The second motor (7, 2) and both motors (//, /J) have a round power transmission system (it, t Housing (D) and housing (D)
10), the movable crab tool KTh-te is equipped with a motor (i
The air inlets (11, 12) of the air supply valve (1)
3;/33) K is connected, the supply valve can automatically move from the closed position to the open position Kf, and the first motor (
11) exceeds the air source pressure by a certain percentage, the air inlet (J-2) of the second cage (12)
) A round air-operated tool for tightening a threaded connection, characterized in that it is arranged to be connected to a source of compressed air. 7 ring hole (3
1:/31) The inside is sealed and guided, and the front C pi first
Claims comprising a valve element (Jも; /75') arranged to be pressurized in the direction of opening of the valve by a counter pressure from a motor (ti'') of the valve and in the direction of closing of the valve by an air source pressure. The movable crab tool according to No. 11iK. 3. The supply valve (73, 77J) is connected to the valve element (iy
;i3) and the valve element (jF;/JP
A moving crab implement according to claim J, comprising a counterbalanced piston ($2/$3) having a surface which is continuously acted upon by atmospheric pressure in the direction of closure of the movable crab. Sail The movable crab device according to claim nb, wherein the balance piston (/$J) has an auxiliary surface (trco) that is pressurized in the opening direction of the valve element (/Jri) by air source pressure. . ! , the balance piston is the valve element (39:/Jri)
A rod coaxial with and fixed to the valve element (4CJ;
/←3) The movable crab tool according to claim 3 or claim V, which is formed by: The valve element has one or more openings (-l; see l) through which air is drawn from a source of compressed air under a certain pressure drop to the first motor (11). Air inlet (J/)
The moving crab tool according to any one of 713. 7. The cylinder hole (3r; 1JI) K is an air inlet port (77; /77) connected to a compressed air source and a first service l communicating with the first motor (//). -) (jG;/jri and the first service port communicating with the first motor (saw)) (j7;/
j7) is provided, and the air inlet day) (37:/
37) and the first service boat (j4; ts4) are never blocked by the valve element (37;/JP)K. L The valve element (Jri;/Jri) is in the cylinder hole (it;
Patent, in which a check valve (jo) is provided, which is connected to a brake piston movably guided in the valve element (3r) and for reducing the braking action in the opening direction of the valve element (3r; 13r). The moving crab tool according to any one of claims λ to 7IJ/1lFc. Father The rod (4117; /Reference 3) is connected to the valve element (4117; /Reference 3).
3; lJ) and supporting said brake piston (≠2) on the low pressure side of the valve element;
IJiKk: A moving crab tool. lo, the housing is equipped with a pistol-shaped grip (1-3) L
, said grip! I) Patent II in which the portable tool comprises a compressed air supply passageway (/4=) for communicating with a source of compressed air (C#) and a hand-actuated throttle valve (I).
+1* Range Any one of items 1 to 2/IJIK: Moving crab tool as described.