JPH0730767B2 - Fluid pressure drive - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a fluid pressure drive device that reciprocally drives a load such as a drill unit and a crown tightening unit by supplying pressure fluid.

(Prior Art) An air cylinder is used exclusively for switching the load body between the working position and the standby position as described above. However, when the load body is driven at high speed, an air cushion, a shock absorber, or the like is used. The load is buffered in the working position.

(Problems to be Solved by the Invention) However, when a load that is driven at high speed is suddenly buffered in a relatively short stroke range such as an air cushion or a shock absorber and stopped at an operating position, a large acceleration occurs, and this large acceleration is generated. There is a problem that a shake occurs due to acceleration until the load body stops at the working position, and it takes too long before the shake disappears.

(Means for Solving the Problem) Therefore, in the present invention, the inside of the cylinder is divided into a drive chamber and a back pressure chamber by a piston housed in the cylinder,
The back pressure chamber communicates with the outside through the throttle passage, and between the piston driven by the supply of the pressure fluid to the drive chamber and the input end of the rotary lever, when the piston reaches the end position of sexual movement. A motion converting means for converting the reciprocating motion of the piston into the rotary motion of the rotary lever is interposed so that the rotary lever is arranged at a position substantially parallel to the reciprocating direction of the piston. Part is engaged with the linear guide part of the driven conversion member, and the guide direction of the guide part of the driven conversion member and the reciprocating direction of the piston are made substantially orthogonal to each other, and the moving direction of the driven conversion member is reciprocated by the piston. A linear guide means that is set substantially parallel to the moving direction is provided, and the guide portion of the driven conversion member is located near the rotation locus position where the tangent line on the rotation locus of the output end of the rotation lever and the reciprocating movement of the piston intersect at right angles. So that the forward end position of It was.

(Operation) When the piston is moved forward by supplying the pressure fluid to the drive chamber in the cylinder, the output end of the rotation lever draws a rotation locus, and the driven conversion member reciprocates by the guide action of the linear guide means. It moves forward in a direction substantially parallel to the direction. While the output end of the turning lever is moving on a turning locus that is substantially parallel to the reciprocating direction of the piston, the driven conversion member moves at the same speed as the moving speed of the output end of the turning lever. . The driven conversion member is about to inertially move in a direction substantially parallel to the reciprocating direction of the piston at this speed, and this inertial movement action propagates to the piston via the output end of the rotary lever.
That is, the inertial movement action acts on the output end of the rotation lever as an acceleration action on the rotation locus, and this acceleration action increases the forward movement speed of the piston. As the forward speed of the piston increases, the pressure in the back pressure chamber in the cylinder increases, and this increase in back pressure acts as a reaction on the driven conversion member via the piston and the rotation lever, and the moving speed of the driven conversion member increases. It converges to zero without causing acceleration.

(Embodiment) An embodiment embodying the present invention will be described below with reference to FIGS.

Reference numerals 1 and 2 denote angle-shaped support frames, and a drill unit 3 is supported on the horizontal portions 1b and 2b so as to be horizontally movable via a guide roller 3a. Drill unit 3
A pair of driven conversion members 4, 5 are provided on the upper side of the support frames 1, 2 along the upright portions 1a, 2a so as to be tightened upright.
The guide grooves 4a, 5a are formed in the vertical direction.

Cylinders 6 and 7 are mounted horizontally on the inner surfaces of the upright portions 1a and 2a of the support frames 1 and 2, and the cylinders 6 and 7 are
Rotation levers 8 and 9 which are rotated by reciprocating rotations of 6 and 7 are attached. Rotors 8a and 9a are attached to the tip ends (output terminals) of the rotary levers 8 and 9, and the rotor 8 that serves as an output end is provided.
The a and 9a are fitted in the guide grooves 4a and 5a of the driven conversion members 4 and 5, respectively. Therefore, when the rotary levers 8 and 9 rotate, the driven conversion members 4 and 5 move horizontally by the guiding action of the linear guide means including the horizontal portions 1b and 2b and the guide roller 3a.

Both cylinders 6 and 7 have the same internal structure. Here, only the internal structure of the cylinder 6 will be described with reference to FIG. Inside the cylinder 6, a pair of cylinder chambers 10 and 11 are vertically arranged side by side. The lower cylinder chamber 10 accommodates a drive piston 12 and the upper cylinder chamber 11 includes a return piston. 13 are housed. Drive piston 12
Divides the cylinder chamber 10 into a drive chamber 10a and a back pressure chamber 10b, and the drive chamber 10a is connected to a pressure air supply source via a pressure air supply pipe 14 and a solenoid three-way valve (not shown). Room
10b communicates with the outside through a throttle passage L1 whose passage cross-sectional area is adjusted by a throttle needle 15. By adjusting the screwing position of the throttle needle 15, the throttle passage L1
The passage area of is adjusted, and the air discharge speed in the back pressure chamber 10b can be adjusted.

The return piston 13 partitions the cylinder chamber 11 into a return drive chamber 11a and a back pressure chamber 11b, and the return drive chamber 11a is connected to the pressure air supply source via a pressure air supply pipe 16 and a solenoid three-way valve (not shown). The back pressure chamber 11b is connected to the throttle needle 17
It communicates with the outside through a throttle passage L2 whose passage cross section is adjusted by. By adjusting the screwing position of the throttle needle 17, the passage cross-sectional area of the throttle passage L2 is adjusted, and the air discharge speed in the back pressure chamber 11b can be adjusted.

Rack portions 12a, 13a are formed on the upper surface of the drive piston 12 and the lower surface of the return piston 13, and a pinion 18 is engaged with both rack portions 12a, 13a at the center of the side surface of the cylinder 6 to rotate. Supported as possible. The rotating lever 8 is connected and fixed to the pinion 18, and the rotating lever 8 is rotated around the pinion 18 by the reciprocating movement of the pistons 12 and 13.
That is, the rack portions 12a, 13a and the pinion 18 are connected to the pistons 12, 13
The reciprocating motion of is converted into the rotation of the rotation lever 8.

When pressurized air is supplied to the drive chamber 10a of the cylinder chamber 10, the drive piston 12 moves to the back pressure chamber 10b side against the back pressure of the back pressure chamber 10b, and the pinion 18 returns the return piston 13 to the return drive chamber.
Rotate clockwise while urging toward 11a. By this rotation, the rotation lever 8 integrally rotates in the clockwise direction, and the rotor 8a draws the rotation trajectory C shown in FIG. A guide groove for the rotor 8a and the driven conversion member 4 moving on the rotation locus C.
The driven converting member 4 is driven by the engaging action with the 4a.
The drill unit 3 is urged in a direction parallel to the reciprocating direction of 12, and the urging action causes the drill unit 3 to move to the horizontal portions 1b, 1b of the support frames 1, 2.
2b is moved in the forward direction of the driving piston 12.

In the initial state, the starting end of the driving piston 12 contacts the inner end surface 10c forming the driving chamber 10a, and after the forward movement, the driving piston 12
Has its tip in contact with the inner end surface 10d forming the back pressure chamber 10b. On the contrary, in the initial state, the tip of the return piston 13 has the back pressure chamber 11b.
Is in contact with the inner end surface 11c forming the
After the forward movement, the starting end of the return piston 13
Is in contact with the inner end surface 11d forming the. Then, when the drive piston 12 is at the end position after the forward movement, the forward end position of the rotor 8a, that is, the driven end, is moved to a position where the tangent line 1 on the rotation locus C and the reciprocating direction of the drive piston 12 are orthogonal to each other. The forward end position of the guide portion 4a of the conversion member 4 is located.
That is, when the piston 12 reaches the forward movement end position, the pinion 18 and the rack portions 12a, 13 are arranged so that the rotating lever 8 is arranged in a position substantially parallel to the reciprocating direction of the pistons 12, 13.
The motion conversion means consisting of a converts the reciprocating motion of the pistons 12, 13 into the rotation of the rotation lever 8.

The driven conversion member 4 has a moving speed that is approximately the same as the speed of the rotor 8a on the rotation locus C near the position of the chain line in the center of FIG. When the rotational speed of the rotor 8a due to the supply of pressure air to the back pressure chamber 10b is maximized in the vicinity of the chain line position in the center, when the driven conversion member 4 passes near the position in the center chain line, the driven conversion is performed. The horizontal inertial movement of the sum of the members 4 and 5 and the drill unit 3 acts on the rotor 8a in reverse, so that the rotor 8a
Is urged in this moving direction. The pitch circle radius of the pinion 18 is r, the turning radius of the turning lever 8 is R, the turning angle of the turning lever 8 is θ, the speed of the driving piston 12 is v, and the moving speed of the driven conversion member 4 is V. Then, the horizontal component V (θ) of the speed of the rotor 8a at the rotation angle θ is expressed by the following equation (1).

V (θ) = Rv · sin θ / r (1) Similarly, the moving speed V of the driven conversion member 4 at the turning angle θ is expressed by the following equation (2).

V = Rv · sin θ / r (2) When the rotation angle θ is displaced to θ + Δθ (Δθ> 0), the equation (1) becomes the following equation (3).

V (θ + Δθ) = Rv · sin (θ + Δθ) / r (3) Assuming that the driven conversion member 4 maintains the speed V at the rotation angle (θ + Δθ), the rotor 8a expressed by the formula (3) Speed V
The difference between (θ + Δθ) and the speed V of the driven conversion member 4 represented by the equation (2) is represented by the following equation (4).

V ([theta] + [Delta] [theta])-V = Rv [sin ([theta] + [Delta] [theta])-sin [theta]] / r (4) Therefore, if [theta]> [pi] / 2, the equation (4) satisfies the following relationship.

V (θ + Δθ) −V <0 (5) That is, the driven conversion member 4 rotates at the rotation angle (θ + Δθ) at the speed V.
Assuming that the above is maintained, the speed of the rotor 8a on the rotation locus C increases. This is because the inertial movement action of the driven conversion members 4 and 5 having the velocity V and the drill unit 3 is the rotor 8a,
9a, the rotation levers 8 and 9 and the pinion 18 to act on the drive piston 12 and the return piston 13, and the inertial movement action increases the speed of the drive piston 12 and the return piston 13.

The back pressure of the back pressure chamber 10b on the cylinder chamber 10 side increases as the speed of both pistons 12 and 13 increases, and the back pressure (negative pressure) of the back pressure chamber 11b on the cylinder chamber 11 side decreases to reduce the back pressure chamber 10b. The pressure fluctuations of 11b act as a braking action for the inertial movement of the driven conversion members 4, 5 and the drill unit 3. As a result, the speed V of the driven conversion member 4 is reduced, and in the state where the rotary lever 8 is rotationally arranged near the position indicated by the solid line in FIG. 2, the back pressure is the inertia of the driven conversion members 4 and 5 and the drill unit 3. It greatly contributes to the movement as a braking action, and is subjected to a smooth deceleration action until the driven conversion member 4 reaches the terminal position of zero velocity shown by the chain line on the left side of FIG. Therefore, the drill unit 3 can be moved and arranged at a predetermined working position with a small negative acceleration that causes almost no shake, and the drill unit 3 can be driven at high speed without using a special buffer chamber.

FIG. 3 is a graph showing an example of the speed relationship between the pistons 12 and 13 and the drill unit 3, and the curve C1 is the piston 1
The speed of 2,13 and the curve C2 represent the speed of the drill unit 3.
The speeds of both pistons 12 and 13 are kept constant up to the position shown in FIG.
Is increased by the inertial movement of the drill unit, and the back pressure fluctuation resulting from this increase in speed acts on the drill unit 3 and the driven conversion members 4 and 5 in reverse.

To return the rotating levers 8 and 9 to the initial position, the cylinder chamber 11
It suffices to supply pressurized air to the return drive chamber 11a.

Of course, the present invention is not limited to the above-described embodiment, and for example, the end positions of the rotary levers 8 and 9 are not limited to π, and fluctuations in back pressure due to the inertial movement action of the drill unit 3 and the driven conversion members 4 and 5. It may be set before the rotation angle position π within an effective working range, or the start end positions of the rotation levers 8 and 9 may be set to the rotation angle position θ> 0.

Further, as shown in FIG. 4, a guide groove 8b is provided in the rotary lever 8, and the rotor 8a is irremovably and slidably fitted and supported in the guide groove 8b, and is rotated in the guide groove 19a of the guide body 19. A configuration in which the child 8a is inserted is also possible. According to this configuration, it is possible to further smoothly decelerate the load body such as the drill unit 3 due to a certain degree of freedom in setting the trajectory of the rotor 8a.

(Effect of the Invention) As described in detail above, the present invention uses the inertial movement action of the load body to increase the back pressure of the drive piston, and reversely uses this increased back pressure for braking against inertial movement of the load body. Thus, it is possible to smoothly decelerate the load body without using a special buffer chamber, and it is possible to drive the load body at a high speed without generating a large acceleration.

[Brief description of drawings]

1 to 3 show an embodiment embodying the present invention.
The drawing is a perspective view, FIG. 2 is a back cross-sectional view of a main part, FIG. 3 is a graph showing a velocity curve, and FIG. 4 is a back cross-sectional view of a main part showing another example. Horizontal parts 1b and 2b and guide rollers 3a which form linear guide means, drill unit 3 as a load body and driven conversion members 4,5, guide parts 4a and 5a, cylinders 6 and 7, turning levers 8 and 9,
Rotors 8a, 9a as output ends, cylinder chamber 10, drive chamber 1
0a, back pressure chamber 10b, drive piston 12, turning locus C, tangent line 1, throttle passages L1, L2.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yasuo Goto 3005 Hayasaki, Kita Sotoyama, Komaki City, Aichi Prefecture CK Day Co., Ltd. Inside Nagoya Machinery Works Co., Ltd.

Claims (1)

[Claims] 1. A piston (12) housed in a cylinder (6, 7) partitions the inside of the cylinder (6, 7) into a drive chamber (10a) and a back pressure chamber (10b), and a throttle passage ( The input end of the piston (12) and the rotation lever (8, 9) which are connected to the outside of the back pressure chamber (10b) via L, 1) and driven by the supply of the pressure fluid to the drive chamber (10a). When the piston (12) reaches the forward end position, the rotating levers (8, 9) are arranged so as to be substantially parallel to the reciprocating direction of the piston (12). Intervening a motion conversion means (12a, 18) for converting the reciprocating motion of 12) into the rotary motion of the rotary levers (8, 9),
The output end portions (8a, 9a) of the rotating levers (8, 9) are engaged with the linear guide portions (4a, 5a) of the driven conversion members (4,5) to move the driven conversion members (4,5, 9). ) The guide direction of the guide part (4a, 5a) and the reciprocating direction of the piston (12) are substantially orthogonal to each other, the moving direction of the driven conversion member (4,5) is the reciprocating direction of the piston (12). Linear guide means (1b, 2b,
3a) is provided so that the tangential line (l) on the turning locus (C) of the output end (8a, 9a) of the turning lever (8, 9) and the reciprocating direction of the piston (12) are orthogonal to each other. A fluid pressure drive device characterized in that a forward movement end position of a guide portion (4a, 5a) of a driven conversion member (4,5) is located near a movement locus position.