JPH10329050A - Reverse direction selection valve with overdrive mechanism and pneumatic tool therewith - Google Patents

Abstract

PROBLEM TO BE SOLVED: To conduct switching to either of forward or reverse direction with a single tool and prevent speed from dropping even when torque increases, in a pneumatic tool containing a reverse direction selection valve with an overdrive mechanism. SOLUTION: This pneumatic tool 10 is provided with a housing 9, a rotor 50 fitted in the housing 9 so as to be rotatable, an output shaft functionally- jointed to the rotor 50, and pressure chambers 19A, 19B, (19C) regulated between the housing 9 and the rotor 50. The pneumatic tool 10 is formed so that a pressurized air flow going to a motor which involves a plurality of chambers may be controlled, so as to keep the rotational direction of the motor in a reverse direction by turning a reverse direction selection valve 20 to select a prescribed position, and to be capable of selecting the number of the pressure chambers which receive the pressurized air.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates generally to a pneumatic tool. More particularly, it relates to a pneumatic tool having a reverse selection valve having an overdrive mechanism for variable torque and variable speed.

[0002]

2. Description of the Related Art Conventionally, various types of reverse selection valves are used in pneumatic tools such as impact wrenches and pulsating tools. For example, Ch given to Giardino et al.
U.S. Patent 5,083, assigned to icago Pneumatic Tool
No. 619 discloses a plunger type reverse selection valve for reversing the rotation direction of a rotor in an impact wrench. U.S. Pat. No. 3,714,994, issued to Zoerner et al. And assigned to Gardner-Denver, discloses a rotary reverse selection valve. This prior art is, for example, Er
As shown in U.S. Pat. No. 3,586,466 to ickson, it further includes an overdrive reverse selection mechanism for the hydraulic motor. The entire contents of any of these patents cited in the present specification shall be referred to in the present specification.

[0003] One of the advantages of pneumatic tools is the ability to obtain both forward and reverse variable torque and speed on the same tool. This is very important when used for construction, demolition or restoration of large structures, such as bridges. For example, one of the long-awaited, unresolved problems with such uses is to obtain increased torque and speed for removing lugs from corrosion, dirt and paint. In general, an operator can use two impact wrenches, a small and lightweight impact wrench and a large and heavy impact wrench. Small and lightweight impact wrenches are used in most lugs to keep workers from getting tired, and are also used because they are easy to operate. Large and heavy impact wrenches are used to remove hard lugs. Such large and heavy impact wrenches are heavy and cumbersome to carry because they only need to remove the hard lugs. In addition, carrying two impact wrenches for use when removing hard nuts is time consuming and inefficient.

Conventionally, variable torque and variable speed hydraulic motors have been known. However, hydraulics have several disadvantages when used on small portable tools. For example, hydraulics have heat generated by friction,
And so on. Another disadvantage is that the hydraulic oil must be filled in a sealed device. If the hydraulic device is not sufficiently sealed, hydraulic oil leaks out of the tool in an oil film form and is lost from the device.

Another disadvantage of hydraulic systems is that as torque increases, speed decreases as disclosed in US Pat. No. 3,586,466. This is because a single chamber between the rotor and the housing is high pressure sealed with an incompressible fluid to rotate the rotor at an initial speed and torque. However, for high pressure sealing of the two chambers, the rotor rotates at increased torque and reduced speed because the hydraulic fluid is not compressible and spreads to fill one space. In contrast, if air is used in the augmented space, it will quickly spread to fill this space. Thus, high pressure sealing of the two chambers with air results in increased torque and increased speed. An analogous useful one is an air-filled balloon that bursts when pierced by a pin. The reason is that the air in the balloon is compressed and moves rapidly to relieve the surrounding air pressure. In contrast, a water-filled balloon does not burst when pierced, but leaks slowly. The reason for this is that the water is not sealed under high pressure.

This related art is directed to a pneumatic tool having a reverse selection valve and a hydraulic motor having a variable speed and a variable torque, but having a variable speed and a variable torque, that is, a reverse direction having an overdrive mechanism. None of the pneumatic tools with a selection valve are covered. Such a device is needed to solve a long-standing and poorly addressed problem in the field of power tools.

[0007]

The advantages of the present invention
Is to solve the above-mentioned drawbacks. To this end, the present invention comprises a housing, a rotor rotatably mounted within the housing, an output shaft operatively connected to the rotor, a pressure chamber defined between the housing and the rotor, A reverse selector valve for a pneumatic tool operatively connected to control the rotor, the reverse selector valve for the pneumatic tool having increased torque, increased speed, And a pneumatic power tool having an overdrive mechanism for providing an output shaft with an overdrive mechanism. Further, the present invention comprises a housing, a rotor rotatably mounted within the housing, and a pressure chamber defined between the housing and the rotor, wherein the reverse select valve for the pneumatic tool is provided. To provide a reverse selection valve for a pneumatic tool having an overdrive mechanism for increased torque and increased speed.

[0008]

One of the advantages of the pneumatic tool of the present invention is that it is possible to obtain increased torque and increased speed in the same tool. This can solve problems when used for building, dismantling or repairing large structures, such as bridges. A further advantage of the present invention is that there are no hydraulic fluid problems. The pneumatic tool does not heat like a hydraulic motor, and is self-cooling by air spreading and cooling through the tool. In addition, pneumatic tools do not require closed mechanisms, as do hydraulic tools which have inherent sealing problems. Air enters the pneumatic tool through the inlet and exits through the outlet. Pneumatic tools do not leak. Thus, the pneumatic tool does not require a complicated sealing structure in the hydraulic motor.

Another advantage of pneumatic tools is that as torque increases, so does speed. Another advantage of the present invention is that the reverse selector valve can control the direction of motor rotation and the overdrive condition in both the forward and reverse directions.

A feature of the present invention is that the reverse selection valve can be configured in various forms. For example, the reverse selector valve may be a plunger valve, and more preferably a rotary reverse selector valve. Alternatively, a combination of a plunger valve and a rotary reverse selection valve may be used.

The rotary reverse selector valve of the present invention includes a rotatable flat member having at least three openings formed therethrough. These holes in the rotatable flat member direct the flow of air through various arrangements to selectively supply pressurized air to one or more ports. For example, the holes can be arranged in a T, y, or Y (ie, Ψ or peace sign) with special holes between the upper holes.

Another feature of the rotary reverse selector valve according to the present invention is that when the reverse selector valve has the form of a rotatable flat member, the reverse selector valve is positioned by an operator. That is, a handle that extends outside the housing of the motor and can be positioned in a rotatable state.

A pneumatic tool according to the present invention includes a pressure chamber defined between a housing and a rotor for providing overdrive characteristics. Each of these chambers has a first forward drive port for receiving pressurized air driving a motor in a forward direction, and a second reverse direction port for receiving pressurized air for driving a motor in a reverse direction. And a drive port. As described herein, other advantages of the present invention also apply to pneumatic tools having any number of pressure chambers surrounding a rotor.

[0014]

BRIEF DESCRIPTION OF THE DRAWINGS The foregoing features and advantages of the invention, as well as other features and advantages, will be apparent from the following more particular description of preferred embodiments of the invention.

Preferred embodiments of the present invention will be described in detail with reference to the following drawings. In this drawing, the same members are denoted by the same reference numerals.

The present invention discloses the use of a pneumatic tool such as an impact wrench, nut runner, or vibrating tool. In particular, for a valve for reverse or overdrive selection according to the present invention, a plunger valve having an axis parallel to the output shaft (see US Pat. For use with various types of pneumatic tools having various reverse selection valve configurations, such as a plunger valve (not shown) and a combined plunger / rotary reverse selection valve (not shown). Is available. Further, the present invention is disclosed by way of example for the use of a rotary reverse selection valve. It is important to note, however, that the present invention appears to be applicable to any reverse selection valve on a pneumatic tool.

FIG. 1 is a full-scale view of a rotary valve according to the present invention, including a first embodiment of a valve 20 for selecting a reverse direction and an overdrive, and a pneumatic hand tool. Is shown. Here, the valve 20 is
It is arranged in a valve housing 12 attached to the rear of the pneumatic tool 10 including the output shaft 60.

In order to select the selective driving state with the valve 20 shown in FIG. 1, the operator turns the valve handle 22 to the selected position. In a detailed embodiment, the operator is provided with a forward position, a reverse position, a forward overdrive position,
And reverse overdrive position. The position representing the selected drive condition is indicated to the operator by an arrow on the valve handle 22 pointing to a marking on the valve housing 12. In the detailed embodiment of the valve, “F” and “R” indicate forward and reverse, respectively, and “FX2” and “RX”
"2" indicates forward overdrive and reverse overdrive, respectively.

Since the valve for selecting the reverse direction and overdrive can be easily understood, the operation inside the pneumatic motor will be described. FIG. 2 shows a rear view of the inside of the valve housing 12 including the valve 20 for selecting the reverse direction and the overdrive according to the first embodiment. FIGS. 3 and 4 show cross-sectional views of the pneumatic power tool including the valve housing 12 taken along lines 3-3 and 4-4 of FIG. 2, respectively.

3 and 4, the pneumatic tool 10 has a motor housing 9 and a valve housing 12. The motor housing 9 has a rotor chamber 51 for rotatably supporting the rotor 50. This rotor 50 is likewise operatively connected to the output shaft 60 of the pneumatic tool 10. An inner housing 30 for limiting the opening to the inside of the motor housing 9 is connected to a rear portion of the motor housing 9. The valve housing 12 is hermetically attached to the rear of the motor housing 9 by bolts (not shown) to take in pressurized air through the opening 14 shown in FIG.

As illustrated by a comparison of FIGS. 9 and 10, the number of pressure chambers 19 provided for driving the rotor 50 may be different sized rotors, higher or lower speeds, or , May be modified to accommodate larger or smaller torques. However, for simplicity of description, the present invention will be described primarily with reference to a housing having two chambers. In order to form the chamber 19, as shown in FIG. 9, the inner periphery of the motor housing 9 is provided with a concave portion 15 alternately spaced in the circumferential direction and a cylindrical surface portion 16. When the rotor 50 is located in the motor housing 9, the pressure chambers 19A, 19B are defined between the rotor 50 and the recess 15. In this alternative configuration, the rotor 50 is positioned within the cylindrical surface 16 for rotation.

The rotor 50 has one or more ports 35, 36, 37, formed in the motor housing.
Driven by pressurized air flowing through. This pressurized air entering through ports 35, 36, 37, 38 causes rotor 50 to rotate by moving a plurality of vanes 54 located in radially extending slots 52 in rotor 50. Has become. Although eight blades 54 are shown here, more or less blades may be used. These vanes 54 are biased outward by pressurized air supplied to the innermost portion of the slot 52 and also by centrifugal force. The outer ends of the blades 54 are kept in contact with the inner periphery of the motor housing 9 regardless of whether the blades 54 are in the cylindrical surface 16 or the pressure chambers 19A, 19B. In order to allow the pressurized air to escape to the surroundings, a plurality of outlets 13 are provided around the rotor chamber 51.
Is provided. The outlet 13 extends into the valve housing 12, as indicated by reference numeral 23A. Describing the motor, each pressure chamber 19A, 19B
Are two ports, the first ports 35, 37
And second ports 36,38. A first port 35, 37 and a second port 36, 38 in each pressure chamber 19A, 19B are located at opposite ends of the pressure chamber. Apply pressurized air to ports 35 and 3
6, 37, 38, an inner housing 30 is provided at the rear of the rotor chamber 51, as shown in detail in FIGS. The inner housing 30 is connected to the ports 35, 36,
A plurality of openings 31, through which pressurized air passes into 37, 38;
32, 33 and 34 are provided.

To support the shaft of rotor 50 (not shown), inner housing 30 also includes bearings 72 with balls 73. Further, the inner housing 3
0 is provided with a circular lip 39 as shown in detail in FIGS.
As described below, the valve housing 12 is directed rearward to orient the valve 20 in a rotatable state.
Extending inward.

The operation will be described.
The first ports 35, 37 of A, 19B, alone or in combination, may be in a first direction (e.g., when compressed air is directed through these ports from each of the inner housing openings 31 and / or 33). The rotor 50 is driven in the positive clockwise direction as shown in FIG. Similarly,
The second ports 36, 38, alone or in combination,
As pressurized air passes through these ports from each of the inner housing openings 32 and / or 34, it drives the rotor 50 in a second direction (eg, in a counterclockwise direction as shown in FIG. 8). . When the two ports are receiving pressurized air, the pneumatic tool 10 is in an overdrive state.

According to the present invention, as shown in FIGS. 1 to 7, which inner housing openings 31, 32, 33, 34
Receives pressurized air from the valve housing 12, and thereby which port 35, 3
To determine if 6, 37, 38 receives pressurized air from the valve housing 12, a valve 20 is provided for selecting reverse and overdrive.

As shown in FIGS. 5-7, valves for motors having two chambers can be of various shapes without departing from the scope of the invention.

In general, the valve 20 comprises a rotatable flat member 18 having a projecting area 21 having a hole, and a handle extension 29. As shown in FIGS.
The valve 20 is rotatably placed in a valve housing manifold 70 of the valve housing 12. Seal 100 seals flat member 18 inside valve housing manifold 70 and seal 110
Seals the handle extension 29 inside the handle opening 74 at the rear of the valve housing 12.
By sealing the valve housing manifold 70 with the seals 100 and 110, the valve housing 12 can receive pressurized air through the opening 14 toward the rotor 50 via the inner housing 30 and the handle 20. The handle extension 29 is provided with a handle 22 as described above for turning the valve 20 outside the front of the valve housing 12 so that an operator can adjust the valve 20.

The valve 20 is rotatably supported around a circular lip 39 on the inner housing 30 to direct pressurized air from the valve housing manifold 70. Perforated projecting area 21 on valve 20
Are provided with one hole 25, 26, 27 extending through the flat member 18 and the projecting area 21. Valve 2
The rotation of 0 causes the inner housing openings 31, 32, 3
3, 34, selectable ports 35, 36, 37,
38 to selectively supply pressurized air to holes
6, 27 are openings 31, 32, 33, 3 of the inner housing.
4 can be aligned. In order to regulate the drive of the motor by pressurized air passing through only one port,
At least one hole 27 is arranged in the following state. That is, this hole 27 is the port 35,
Valve 2 in line with one of 36, 37, 38
0 is positioned. Further, at least two holes 2 are provided to adjust the overdrive characteristics by supplying pressurized air through two ports.
5, 26 are provided on opposite sides and also equidistant from the axis of the valve 20. For example, as shown in FIG.
Holes 25, 26 allow pressurized air to flow through second ports 36, 38.
Openings 3 in the inner housing, respectively.
Align with 2,34.

As shown in FIGS. 5 to 7, the positioning of the projecting area 21 having a hole, and thus also the hole 2
5, 26, 27, holes 125, 126, 127 and hole 2
25, 226, and 227 can be variously positioned. By changing the positions of these holes, the position of the handle 22 of the valve 20 can be changed. For example, as shown in FIG. 1, the valve 20 of FIG. 5 is aligned with a predetermined position of the valve 20 by arranging a projecting region 21 having a hole in a substantially y-shape. In FIG. 6, the valve 120 has four holes 125 such that a fourth hole is positioned equidistant between the Y-shaped upper branches (ie, Ψ-shaped or piece-signed). , 1
26, 127, and 128. In FIG. 7, the valve 220 has three holes 225, 2 arranged in a substantially T-shape.
26 and 227 are provided.

The number of holes in the valve, and thus the number of valve positions that can be selected, is determined by the number of chambers in the motor. In a motor having two chambers, it is shown that the valve 20 can be positioned in at least four positions, as shown in FIG. The position is, for example, the first port 3
5 to drive the motor in the forward direction through
7 is in a first position in air communication with the inner housing opening 31, the valve hole 27 for driving the motor in the opposite direction through the second port 38 is provided in the inner housing opening 3.
4 in a second position in air communication with second port 3
Through a third position in which the valve holes 25,26 are in air communication with the inner housing openings 32,34, and through the first ports 35,37 to drive the motor in the reverse overdrive condition through 6,38. The hole 25 of the valve for driving the motor in the forward overdrive state,
26 is a fourth position in air communication with the openings 31, 33 of the inner housing. FIGS. 8 and 10 show that the motor according to the invention may have more than two chambers, each chamber containing first and second ports. As can be seen from FIG. 10, all of the first and second ports are equidistantly positioned around the rotor chamber (all of the first ports are 120 ° apart from each other and the second port is Are 120 ° apart from each other.)

As shown in FIG. 8, a rotary valve used for a motor having three chambers has (1) a hole 327,
(2) holes 325, 326, and (3) holes 328, 329, 3
It has three sets of 30 holes. Hole 328,
The sets of 329, 330 are equidistantly positioned (120 ° apart from each other), and when the valve is positioned in the proper position (fully overdriven), all of the forward and reverse directions can be used. Are capable of receiving pressurized air. In addition, holes 32
5, 326 are positioned around the valve 120 ° apart from each other so that the two chambers can receive pressurized air in either forward or reverse direction (medium overdrive condition). . The third hole 327 is
One chamber is positioned to receive pressurized air.

Hole 327, hole 325, 326 and hole 3
Each set of 28, 329, 330 is positioned so as not to interfere with the operation in the other hole sets. In other words, a predetermined set of holes is selected to supply pressurized air to one, two, or three ports, while holes other than these predetermined sets are pressurized to any of the other ports. It is positioned so as not to supply air. Thus, in this alternative embodiment, the valve can be positioned in at least six positions. That is, the first position allows flow to a first port in any one of the pressure chambers, and the second position allows flow to a second port in any one of the pressure chambers. And The third position is any one of the two pressure chambers.
The fourth position allows flow to the first port at one of the pressure chambers and the fourth position allows flow to the second port at any two of the pressure chambers. Furthermore, the fifth position is
The sixth position allows flow to the first port in all pressure chambers and the sixth position allows flow to the second port in all pressure chambers.

Although the present invention has been described in relation to the specific embodiments outlined above, it is evident that many other embodiments, modifications and variations will be apparent to those skilled in the art. is there. Therefore, the preferred embodiments of the present invention as described above are used for convenience of description and are not intended to be limiting. Various modifications are possible without departing from the spirit and scope of the invention as defined in the following claims. For example, the device should not be limited solely to using air, as other gases may be applied.

[Brief description of the drawings]

FIG. 1 is a full-scale view showing a pneumatic hand tool including a rotary reverse selection valve and an overdrive selection valve according to an embodiment of the present invention.

FIG. 2 is a rear view showing the inside of a valve housing including the valve according to the first embodiment of the present invention.

FIG. 3 is a cross-sectional view of the valve housing taken along line 3-3 of FIG. 2 according to the present invention.

FIG. 4 is a cross-sectional view of the valve housing taken along line 4-4 of FIG. 2 according to the present invention.

FIG. 5 is an original view of a valve according to the first embodiment of the present invention.

FIG. 6 is a full-scale view of a valve according to a second embodiment of the present invention.

FIG. 7 is an original view of a valve according to a third embodiment of the present invention.

FIG. 8 is an original view of a valve according to a fourth embodiment of the present invention.

FIG. 9 is a rear view of the motor chamber according to one embodiment of the present invention.

FIG. 10 is a rear view of a motor chamber according to another embodiment of the present invention.

FIG. 11 is a front view of the inner housing of the motor according to the present invention.

FIG. 12 is a side view of the inner housing of the motor according to the present invention.

FIG. 13 is a rear view of the inside housing of the motor according to the present invention.

[Explanation of symbols]

Reference Signs List 9 motor housing 10 pneumatic tool 12 valve housing 13 outlet 14 opening 15 recess 16 cylindrical surface portion 18 flat member 19 pressure chamber 20, 120, 220 valve 21 projecting area 22 valve handle 25, 26, 27 hole 29 handle extension Reference Signs List 30 inner housing 31, 32, 33, 34 opening 35, 36, 37, 38 port 39 circular lip 50 rotor 51 rotor chamber 52 slot 54 blade 60 output shaft 70 valve housing manifold 72 bearing 73 ball 74 handle opening 100, 110 seal 125, 126, 127, 128 hole 225, 226, 227 hole 325, 326, 327, 328, 329, 330
Hole

Claims (19)

[Claims] 1. A housing, a rotor rotatably mounted within the housing, an output shaft operatively connected to the rotor, a pressure chamber defined between the housing and the rotor, and the rotor. A directional control valve for a pneumatic tool operatively connected to control the air flow, wherein the reverse select valve for the pneumatic tool provides increased torque and increased speed. A pneumatic tool having an overdrive mechanism applied to the output shaft. 2. The system of claim 1, further comprising an input port operatively connected to the reverse selection valve for the pneumatic tool, and an exhaust port for exhausting air from the pressure chamber. Pneumatic tools. 3. The pneumatic tool according to claim 1, wherein the reverse selection valve for the pneumatic tool is a rotary reverse selection valve, and the rotary reverse selection valve is rotatable about a shaft. 4. The pneumatic tool according to claim 3, wherein the rotary reverse selection valve is a flat member and includes at least three holes through the flat member. 5. The pneumatic tool according to claim 4, wherein two of said at least three holes are on opposite sides and are equidistant from said axis. 6. The pneumatic tool according to claim 5, wherein the holes are arranged in a substantially T-shape. 7. The pneumatic tool according to claim 5, wherein the holes are arranged in a substantially y-shape. 8. The method according to claim 1, wherein the hole includes four holes, and three of the holes.
6. The pneumatic power tool according to claim 5, wherein one of the plurality of holes is arranged in a substantially Y shape together with a fourth hole, and the fourth holes are arranged at equal distances between the Y-shaped upper branch portions. . 9. The pneumatic tool according to claim 3, wherein the rotary reverse selection valve further includes a handle that can be positioned so as to rotate with respect to the outside of the housing. 10. The pneumatic tool according to claim 1, comprising two pressure chambers. 11. A reverse selection valve for a pneumatic tool comprising a housing, a rotor rotatably mounted within the housing, and a pressure chamber defined between the housing and the rotor. A reverse selection valve having an overdrive mechanism for increased torque and increased speed. 12. The valve according to claim 1, wherein the reverse selection valve is a flat member and has at least 3
The pneumatic tool according to claim 11, comprising two holes. 13. The pneumatic tool according to claim 12, wherein the holes are arranged in a substantially T-shape. 14. The pneumatic tool according to claim 12, wherein the holes are arranged in a substantially y-shape. 15. The hole includes four holes, three of which are arranged in a substantially Y-shape with a fourth hole, wherein the fourth hole is formed in the Y-shaped upper branch portion. 13. The pneumatic tool according to claim 12, wherein the pneumatic tools are arranged at equal distances between them. 16. A system comprising at least two pressure chambers comprising a housing and a rotor and defined between said housing and said rotor, each pressure chamber moving said rotor in a first direction. A pneumatic tool comprising: a first port for receiving pressurized air for driving the rotor in a second direction; and a second port for receiving pressurized air for driving the rotor in a second direction. A pneumatic tool comprising a valve for selectively controlling the flow of pressurized air toward one or more of the first ports, or toward one or more of the second ports. 17. The flow directed to any of the second ports when the valve is selected to control the flow of pressurized air directed to one or more of the first ports. And the selection of the reverse selection valve to control the flow of pressurized air toward one or more of the second ports is performed when the reverse selection valve is selected. The pneumatic tool according to claim 16, wherein flow toward any of the first ports is blocked. 18. A first pressure chamber comprising first and second pressure chambers, wherein said reverse selection valve allows flow to said first port in said first or second pressure chamber. Position, a second position allowing flow to the second port in the first or second pressure chamber, enabling flow to the first port in the first or second pressure chamber 17. The method of claim 16, wherein the second position is positionable in one of a third position, a fourth position allowing flow to the second port in the first or second pressure chamber. Pneumatic tools. 19. The apparatus of claim 19, further comprising a first, a second, and a third pressure chamber, wherein the reverse selection valve allows flow to the first port in any one of the pressure chambers. A first position, a second position to allow flow to the second port in any one of the pressure chambers, a flow to the first port in any two of the pressure chambers A third position to allow flow to the second port in any two of the pressure chambers; a flow to the first port in all of the pressure chambers A fifth position, a sixth position allowing flow to the second port in all of the pressure chambers.
The pneumatic tool according to claim 16, wherein the pneumatic tool can be positioned at one of the following positions: