TWI220117B - Speed adjustment mechanism for a pneumatic grinder - Google Patents

Abstract

Disclosed is a speed adjustment mechanism for a pneumatic grinder, comprising: a shaft forming a passage therein; a plurality of air guiding apertures defined on a periphery of the shaft and communicating the passage; a speed adjusting base mounted to the shaft and rotatable with the shaft; a plurality of sliding members respectively received in sliding channels formed in periphery of the speed adjusting base; a speed adjusting disc, having a flange protruding forwards from a periphery of a circular disc body; an annular flange protruding rearwards from a rear end of the disc body, the annular flange being formed with a plurality of air holes on a periphery thereof; the speed adjusting disc being fit over the shaft and slidable along the shaft and rotatable in unison with the shaft; the speed adjusting disc having a wall fit over an outer periphery of the speed adjusting base; the air holes corresponding to the air guiding apertures; a resilient member, resiliently urging against the speed adjusting disc. Under a normal state, the air holes align with the air guiding apertures. When the speed adjusting mechanism over-rotates, centrifugal effect of the sliding members pushes the speed adjusting disc rearwards to cause misalignment between the air holes and the air guiding apertures.

Description

1220117 (1) [Explanation of the invention] [Technical field to which the invention belongs] The present invention relates to a pneumatic tool-related grinder, and its speed regulating mechanism can stabilize the pneumatic rotation speed without following the high-pressure gas pressure mechanism without malfunction. [Previous technology], in detail, refers to the rotational speed of a pneumatic research tool, which greatly changes the power of the pneumatic tool, and the adjustment, as shown in the first figure, is equipped with one (16) and the other (1 4) synchronization Later, the high-pressure whitening of several 'hunting belts' due to the speed of the aerodynamic rotor (14), that is, as soon as the rating was exceeded, a tuning shaft was equipped with a shaft (22) and a speed lever (24). The inner part is provided with a grinding disc and a rotor into the pneumatic tool room (1Ό, the sub (1 4)). Therefore, 'the higher the supply, the rotor's rotation will be even when the rotation speed of the rotating tool. ， ， Fixed to the set of one pneumatic spring (27) = two set of pneumatic guards, such as those shown in the figure (10) of the grinder or sander, turn t04) on its shell, 1 Hai The shaft of the car (the upper part is equipped with an air chamber inside the casing (12) (the middle part is equipped with a rotating speed regulating mechanism (2Q). The high-pressure gas is guided to the lice through an air inlet (18) to enter the air I, the mouth (19) is built into the air cylinder (ι3) and driven to rotate, and the "Hai abrasive sheet (16)" rotates to grind the object. Ye Xikou Sujun It will affect the pressure of high-pressure gas, and the pressure value of gas is not constant. When the rotation speed of the pressure is increased, on the other hand, the pressure decreases when the pressure decreases. As the abrasive disc (16) has the rated rotation speed, there will be cracks. Dangerous, so this type of air speed mechanism (20), in order to prevent the speed of the rotor from exceeding the speed of the speed mechanism (20), such as the second, third and cup (2 2), a speed control rod (2 4), tied straight A stopper (26), which is at the end, can slide, and the stopper (26) is subject to

1220117 Five 'invention description (2) elastic support; two speed-adjusting blocks (28) are pivotally connected to the recesses (241) of the speed-adjusting end, respectively, and the pivoting ends of each speed-adjusting rod (28) are ,, ^ (281), can be shaped like the end face of the stopper (26). The speed regulating mechanism is fixedly connected to the rotor (4) by the beautiful end of the shaft (2 2), but the end of the stopper (26) is directly opposite the air inlet (18), and rotates as shown in the first figure 'When the rotor (14) is not rotating, the stopper (26) is pushed upward and keeps sliding forward, and the two speed-adjusting blocks (28) are not outwardly pushed and pushed. When the rotor rotates, the speed regulation mechanism (20) rotates synchronously. ^ Brother = the free end of the speed block (28) is opened due to the effect of centrifugal force, as shown in the fourth figure ^-= the tip of the speed block (280 It moves the stopper (26) to move backwards, so that the distance between the stopper (26) and the air inlet (18). Therefore, when the air pressure value becomes large and the rotation speed of the rotor increases, the speed control block (28) The opening angle also follows, so that the stopper (26) is moved further toward the air inlet to block the flow of high pressure σ to prevent the rotor from rotating too fast. However, the research of the inventor found that the upper The unveiling structure has many unanticipated points that need to be further improved: As shown in the second figure, because the speed governing mechanism (20) is longitudinal and overall, the two longitudinal sections ( A) The outermost system forms a milking point (b) 'It forms an air-blocking effect on the direction of high-pressure gas flow, which causes turbulence and causes the speed-regulating mechanism to stagnate, resulting in the phenomenon of aerodynamic vibration. In the actuated state of the fourth picture, the speed control block (28) uses its tip (280 to move the stopper due to centrifugal action). 26) displacement, the stop of movement of the line with a direction parallel to the intake of the high pressure gas, the intake pressure for direct use as a front line

Page 6 1220117, description of the invention (3) 々 々 § (2 6), so that the speed control block (2 8) completely withstand the intake pressure ^ Therefore, the 5 Hai tip (2 8 1) is subjected to high loads . Because the tip is an acute angle, the a leaf is easy to wear. When the tip is worn to a certain extent, the length of the tip becomes shorter. 'The stopper cannot be turned (2 6), and the efficiency of adjusting the rotor speed is lost. The block (28) may also be stuck with the stopper (2 6) as shown in the fifth figure when an inappropriate offside occurs. All of these cause malfunctions. 3. For the processing of the speed governing mechanism, the speed governing lever (24) is

Long rod-shaped, the two hollow recesses (241) are cut by double turning. Due to the hollow structure formed after processing, it is easy to generate thermal strain during heat treatment, which causes the symmetry of the two ends of the speed control rod to change, and it is easy to produce when rotating vibration. Similarly, the stopper (26) is a thin piece, and it is easy to generate thermal strain after heat treatment, which affects the concentricity, causes interference friction between the stopper (26) and the shaft (22), and affects the operation. T 4. According to the design of the speed control mechanism (20), it can be seen that the stopper (26) directly resists the pressure gas and bears the pressure. Therefore, even under normal pressure, the components of the speed control mechanism always bear the pressure. The effect of air pressure starts to wear. 5. Because the stopper (26) directly bears the pressure of high-pressure gas, when the air pressure value is large, the stopper is difficult to move backward, and the speed regulating block (28) is difficult to swell out, causing its speed regulation effect to be ineffective. Chang. The test by the inventor found that when the air intake pressure is higher than 90 psi, as shown in the sixth figure, as the air intake pressure increases, the speed regulation of the speed regulation mechanism: instead, the speed of the rotor is greatly increased, so The speed governing mechanism cannot effectively control the rotation speed of the rotor.

1220117 V. Description of the invention (4) [Faday, month, and month] This is a kind of pneumatic grinding speed. This issue M This speed regulation The present invention can be reduced [Implemented to make μ and the β pattern reached in detail The first diagram The second diagram The third diagram The fourth diagram The fifth diagram The fifth diagram The sixth diagram. The seventh figure, the eighth figure, the ninth figure, the tenth figure, and the eleventh structure. [Another lesson of another institution that aims to solve the problem] The effect of your review is shown in the display system, the display system, the second system The second display shows that the seventh series of the current series is the seventh intake member that is the same as the graphic series. The main purpose of Jiu Shi Pei is to provide a structure that can effectively control the rotation of the pneumatic grinder. It is to provide a pneumatic grinder with a smooth and reasonable speed governor that will not cause malfunction. It is to provide a loader for the pressure of a governor of a pneumatic grinder. The purpose and characteristics of the present invention can be further understood. A preferred embodiment of the present invention will be described below, and the arrangement of the drawings is as follows: A schematic diagram of the structure of a grinder. Front view of speed governing mechanism. Right side view. Active state. Figure shows the state of malfunction. Rotating speed and high pressure gas pressure value of the dynamic grinder. Exploded perspective view. Longitudinal section. The figure shows its operating state. . After the invention, the speed of the pneumatic grinder and

1220117 V. Description of the invention (5) Relation diagram of high pressure gas pressure value. First, please refer to the seventh and eighth figures, which are the speed governing mechanism (30) of the pneumatic grinder provided by a preferred embodiment of the present invention, which includes: a shaft (40), the end of which is axially inward A channel (42) is provided, and the channel does not penetrate to the front end of the shaft; four air guide holes (44) are arranged on the circumference of the shaft (40) at equal intervals in the same circle, and communicate with the channel radially ( 4 2) 'As shown in the ninth figure. A speed adjusting seat (50) is a circular body, and its shaft hole (52) is fixed to the shaft (40), and can be synchronously rotated with the shaft. Front of the air guide hole (4 4). Three slideways (5 4) are arranged at equal intervals on the circumference of the speed regulating seat (50), and are recessed radially inward. The three sliding members (5 5) are beads, and are respectively accommodated in the slides (5 4), and can be displaced along the slides. A governor plate (60) has a circular plate body (62) and a plate wall (β 4) protruding forward from the periphery of the plate body (6 2), and the interior of the plate wall (6 4) is formed. A recessed space, and a cone surface (6 6) inclined forward and outward is provided on the inner periphery of the disk, as shown in the ninth figure; a set of holes (68) penetrates the center of the disk body (62) in the axial direction; A convex ring (70) protrudes rearwardly from the periphery of the sleeve hole (68) from the rear end surface of the disc body (62). The peripheral edge of the convex ring (70) is provided with four through-air ports (72) at equal intervals. The speed adjusting disc (60) is sleeved on the shaft from the rear end of the shaft (40) with the sleeve hole (β8), and can be slid along the shaft. 6 4) and cover the outer periphery of the speed adjusting seat (50), and cover the speed adjusting seat in the recessed space of the speed adjusting disc, and the sliding members (55) can contact the plate gap (64 ) The inner cone surface (66); the four air ports (7 2) are facing the four air guide holes (4 4), as shown in the ninth figure. A positioning 1220117 V. Description of the invention (6) One end of the pin (7 5) is inserted into the pin hole (4 7) of the shaft (4 0), and the other end is embedded in the convex ring (7 0) An axial recess (7 4) is provided on the inner wall, so that the speed control disc (60) can be rotated synchronously with the shaft (40), and the speed control disc can be slid along the shaft. An adjusting member (80) is a nut, and its screw hole (82) is screwed to the threaded portion (4 6) at the rear end of the vehicle lever (40). A top fixing piece (85) is a screw, which is set in a through hole (84) provided in the radial direction of the adjusting piece, and must be tightly pressed against the shaft (40), as shown in the ninth figure, to locate the Adjusting piece (80).

A bullet yellow (90) is sleeved on the shaft (40), and its two ends are respectively abutted on the adjustment piece (80) and the speed control disc (60), so that the speed control disc is not subjected to external force. At that time, keep sliding forward, and position it against the speed regulating seat (50). The speed regulation mechanism (30) of Haihai is installed in the air chamber (100) of the pneumatic grinder as shown in Figure 9 and is fixed to the front end (48) of the shaft (40). The rotor can rotate with the rotor. The passage (4 2) at the end of the shaft is directly opposite the high pressure gas inlet (1 0 2). When adjusting the position of the adjusting member (80) on the shaft, the spring force of the spring (90) to hold the speed dial (60) can be adjusted. In a normal state, the speed adjusting disc (60) is positioned against the speed adjusting seat (50), and the air ports (72) are completely aligned with the air guiding holes (44).

When high-pressure gas is introduced into the air inlet (102) of the pneumatic grinder, the high-pressure gas system directly flows into the channel (42) of the shaft (40), and then passes through the air guide holes (44), air ports ( 72) and flows into the air chamber (100), flows from the vent (104) to the rotor 'to drive the rotor to rotate, and the speed regulating mechanism (30) also rotates with it. When the speed of the rotor is in the normal range, that is, when the intake air pressure is at the normal value, the centrifugal force of the slippers (55) cannot overcome the

1220117 V. Description of the invention (7) Elastic yellow (90), elastic energy, and the governor (60) cannot be displaced. Therefore, the air guide holes (44) and the air ports (72) remain in a state of facing, which will not hinder The state of circulation of compressed air. § In the case where the rotor speed is increased due to too high intake pressure, the centrifugal force of the moving parts (5 5) moving out of the slide (5 4) acts on the cone of the speed control disk (60) (6 6) 'and push the speed control disc (6 q) to move backward. At this time, the two displacement forces are greater than the elastic energy of the spring (90), so the speed control disc (60) is as shown in the tenth figure. The state shown is shifted backward, making the air hole (44) and the air port ^ difference in position, reducing the air flow path between the air hole and the air port, the gas flow into the air chamber (100) is reduced, thereby reducing Rotor speed prevents the rotor from rotating at excessive speed.俟 When the air inlet pressure value reaches the normal range, the centrifugal effect of these sliding members (55) is not enough to promote the displacement of the speed control disk (60). As shown in the normal two == (/ 〇) to change the holding force of the bomb *, the intake air pressure value that causes the speed regulation i (60) to begin to shift can be adjusted. The invention has the following effects: The invention is designed in the form of a circular object, so it does not have a gas-cutting effect on gas = 1 t in the room. As can be seen from the ninth figure, the compressed gas is in the air and runs along the outer periphery of the disc speed disc. Flow, the speed governing mechanism does not appear: 1 "turbulent flow state", so 'the present invention does not produce air resistance or choking phenomenon' can improve the vibration phenomenon of pneumatic tools. The present invention controls the position difference between the air guide hole and the air port State and cover-flow 'This type of action is reasonable and effective, and will not cause a load on the structure 1220117 V. Description of the invention (8), so no malfunction will occur. 3. The components of the invention are circular structures Shape is easy to manufacture, and the component is not easy to generate thermal strain after heat treatment. To maintain a good concentricity and symmetry improve the stability and smoothness.

4. The high-pressure gas system directly enters the channel of the shaft and flows from the air guide holes and air ports into the air chamber. Therefore, the load of the high-speed gas by the speed regulating mechanism is greatly reduced; in addition, the air guide holes and air ports are used to block the air flow. At this time, the air flow is blocked in a direction perpendicular to the flow direction of the air flow and in a horizontal state, so the effect of the impact of compressed gas can be reduced. Therefore, the present invention does not withstand the load of high-pressure gas, which can reduce the wear state of components. Fifth, the invention does not produce air-blocking effect, does not cause turbulence, and is not directly impacted by high-pressure gas, making the operating state of the invention more reliable. The test result of the inventor's physical test is shown in Fig. 11. It can be seen that the present invention can effectively stabilize the rotation speed of the rotor even when the pressure value of the high-pressure gas has greatly changed.

Page 12 1220117 Brief description of the drawings The first diagram shows the structure of a pneumatic grinder. The second figure is a front view showing a conventional speed regulating mechanism. The third picture is a right side view of the second picture. The fourth picture is the operating state of the second picture. The fifth picture shows a state where a malfunction occurs in the second picture. The sixth figure shows the relationship between the rotating speed of the conventional pneumatic grinder and the pressure value of the high-pressure gas. The seventh figure is a rear perspective view of a preferred embodiment of the present invention. The eighth figure is an exploded perspective view of the seventh figure. The ninth figure is a longitudinal sectional view of the seventh figure. The tenth figure is similar to the ninth figure, showing its operating state. The eleventh figure is a graph showing the relationship between the rotational speed of the pneumatic grinder and the pressure value of the high-pressure gas after the invention is installed. Brief description of drawing number: Shaft (4 0) Speed governor (50) Speed governor (6 0) Cone (6 6) Locating pin (7 5) Spring (90) Channel (42) Slide (54) Plate body (62) Convex ring (7 0) Recessed groove (74) Speed regulating mechanism (30) Air guide hole (44) Slider (5 5) Coil wall (6 4) Air port (72) Adjusting member (8 0)

Page 13

Claims (1)

Sixth, the scope of patent application1. One type of rotor, and a shaft air guide hole, the front end of the rotating rod is rotated synchronously with a speed adjustment, the slideway, etc. are equal to ', and it can be extended along the slide with a speed adjustment. Hole, along the axis 1 Hai rear end of the plate is dedicated to guide the air hole set on the shaft to adjust the plate of the disk 曰 said inner hole; a flexible club sliding in front of it, hunting this, fluorine hole; when the cone surface, and The speed regulating mechanism of the pneumatic grinding machine is connected to the pneumatic grinding machine and rotates with the rotor, and includes:, the end of which is set in the axial direction inward / channels at a predetermined number of equal intervals on the peripheral surface of the shaft, And the radial passage communicates with the channel; the sun is used to connect to the rotor; the seat is a circular body, which is fixed on the shaft 'and can be located along the shaft with the speed regulating seat and in front of the air guide holes; a predetermined number of The partition is provided on the circumference of the speed regulating seat; the sliding parts of the slideways are respectively accommodated in the middle lanes of the slideways. The discs have a circular disc body and a direction from the periphery of the disc body. The inner periphery of the plate is a tapered surface that slopes forward and outward. J runs through the center of the plate. · 'A convex ring, which protrudes backward from the peripheral surface of the sleeve hole, and the peripheral edge of the convex ring is provided with an equal number of air ports at equal intervals; It can slide along the shaft and rotate synchronously with the shaft; the gap is sheathed on the outer periphery of the speed regulating seat; the sliding parts can contact the conical surface of the circumference; the air ports respectively correspond to the The air guiding element is elastically supported on the speed regulating disc, so that the speed regulation is kept against the speed regulating seat to be positioned; under normal conditions, the air ports are directly opposed to the speed guiding, The centrifugal action of the sliding parts will act on the moving of the speed control disc to move backwards, so that the air ports and the air-guiding shapes are 1220117. 6. The scope of patent application is in a position difference. 2. The speed governing mechanism described in item 1 of the scope of patent application, further includes: an adjusting member, which is arranged on the shaft, located behind the speed control discs, and can be adjusted to be located in the axial direction of the shaft One end of the elastic element is supported by the speed regulating disc, and the other end is supported by the adjusting member; 3. The speed regulating mechanism according to item 2 of the scope of patent application, wherein: behind the shaft The end peripheral surface is provided with a thread, and the adjusting member is a nut, which is screwed to the rear end of the shaft. 4. The speed governing mechanism as described in item 1 of the scope of patent application, wherein: the inner wall of the convex ring of the speed governing disc is provided with an embedded groove along the axial direction; it also includes: a positioning pin whose one end is inserted in The shaft has a peripheral surface, and the other end is embedded in the slot. Page 15