JPH0233841B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an air motor that operates using compressed air as a driving force.

Conventionally, relatively small air motors have been known that drive rotating vanes using the supplied dynamic pressure and expansion pressure of compressed air. When used in , the torque of the output shaft was low and unstable, making it difficult to start with a load applied. In order to use it without such problems, the output shaft must be driven at high speed (for example, several thousand to tens of thousands of rpm) and then sufficiently decelerated, and even if the motor itself is small, a large speed reduction device is required. Therefore, the effect of using a small motor would be halved. By the way, Japanese Patent Application Laid-open No. 54-120338 discloses that two sets of rotary drive mechanisms are provided in which an output shaft is rotationally driven by a double-acting air cylinder via a rack rod, a pinion, and a one-way clutch. A pneumatic motor is described in which the output shaft is rotated continuously in one direction by alternately rotating the output shaft using a mechanism.

This pneumatic motor is superior in that it can drive the output shaft to rotate continuously using two sets of double-acting air cylinders, but it has a mechanism that rotates the output shaft only in one direction and drives the output shaft to rotate in the opposite direction. As a result, the applications of pneumatic motors are severely restricted and lack versatility.Additionally, if a rotation drive mechanism for reverse rotation drive is added, the entire pneumatic motor becomes extremely complex and large, lacking practicality. There are other problems. In addition, the pneumatic motor of the above-mentioned publication does not have a cohesive, integrated form as a pneumatic motor, and even if various parts are incorporated inside the housing etc., the pneumatic motor as a whole is not well-organized, is large, and lacks practicality. There is.

This invention utilizes a reciprocating motor that performs linear reciprocating motion using compressed air, so the torque of the output shaft is stable even at low rotation speeds, and the compact air motor is capable of delivering maximum torque from the start. The purpose of this invention is to provide an air motor that can be switched between forward and reverse rotation.

Embodiments of the present invention will be described below based on the drawings.

Figures 1 and 2 show the entire air motor, which consists of a linear reciprocating mechanism 1 and a rotation conversion mechanism 2 that converts linear reciprocating motion into rotational motion, both of which are integrally connected by bolts 3... has been done.

The linear reciprocating mechanism 1 includes a cylinder case 1a.
The control case 1b and the connection case 1c are connected to both ends of the control case 1b. The control case 1b is provided with a compressed air supply port 4 and an air discharge port 6 with a muffler 5, and a piston 7 is installed inside the cylinder case 1a and the connection case 1c, and the connection case 1c is also provided with compressed air. A supply port 8 is provided.

A control rod 9 extends from one end of the piston 7 and is inserted into the control case 1b, and a rack rod 10 extends from the other end of the piston 7 and is inserted into the rotation conversion mechanism 2.

Inside the control case 1b, an annular passage a communicating with the air supply port 4, a communication passage c connecting the annular passage a and the piston chamber b, and an annular passage a communicating with the communication passage c are formed. A valve 11 is provided for shutting off the pilot working chamber. or,
An annular groove 12 is formed in the middle of the control rod 9, and as shown in the figure, the air pressure when the piston 7 is at the left stroke end flows through the flow path d and the annular groove 1.
2, the valve element 11 is moved to the right due to the difference in the left and right pressure receiving areas of the valve element 11, and the annular passage a and the communication passage c are blocked, and the communication passage c is connected to the discharge port 6 through a flow path e in the valve 11. In this state, the piston chamber b is communicated with the atmosphere, so the piston 7 is driven to the right by air from the other compressed air supply port 8.

When the piston 7 reaches the right stroke end, the left pressure receiving surface of the valve element 11 is connected to the control rod 9.
The air pressure is connected to the discharge port 6 through the rod insertion gap f in the valve element and the annular groove 12, and air pressure acts only on the right pressure receiving surface of the valve element 11, and the valve element 11 is moved to the left. This connects the annular passage a and the communication passage c, and the same air pressure acts on both left and right sides of the piston 7.

Here, the right side pressure receiving surface _S1 of the piston 7 is set to have an area twice that of the left side pressure receiving surface _S2 , and the piston 7 is driven to the left by the area difference. In this case, the difference in area between the left and right pressure receiving surfaces S ₁ and S ₂ is equal to the area of the left pressure receiving surface S ₂ , so if the supplied air pressure is constant, the piston driving force to the right and to the left is the same. Become.

As described above, one reciprocating operation is completed, and the same operation is repeated thereafter, so that the rack rod 10 is reciprocated with a constant stroke.

In other words, the linear reciprocating mechanism 1 operates in a state in which air pressure is simultaneously applied to the left pressure receiving surface S ₂ of the piston 7 and the right pressure receiving surface S ₁ which is twice the size of the left pressure receiving surface S ₂ . The piston 7 is configured to reciprocate with a constant driving force by automatically switching between a state in which air pressure is applied only to the piston 7 as the piston 7 moves.

The principle structure of this linear reciprocating mechanism 1 is shown in FIG.

The configuration of the rotation conversion mechanism 2 will be explained next.

An output shaft 16 is supported via bearing brackets 14 and 15 on the front and rear walls of a box-shaped case 13 connected to the connection case 1c of the linear reciprocating mechanism 1 with bolts 3. The rods 10 are arranged in an orthogonal position. Frame plates 17a and 17b of the same shape are loosely fitted and supported on both bearing brackets 14 and 15, respectively, so as to be rotatable around the output shaft axis.
a, 17b are connected at a constant interval by stays 18..., and these frame plates 17
A pair of rotating shafts 19a and 19b located on the left and right sides of the output shaft 16 are rotatably supported between the shafts a and 17b.

Each rotating shaft 19a, 19b has a pinion gear 20a, 2 which can engage with the rack 10a of the rack rod 10.
0b is integrally formed, and intermediate transmission gears 22a, 22b are externally fitted via one-way clutches 21a, 21b having opposite characteristics, and these intermediate transmission gears 22a, 22b form an output gear 23 integrally formed on the output shaft 16. It is always in occlusion.

In addition, the front frame plate 1 is attached to the bottom wall of the case 13.
A pair of pistons 24 are located opposite to each other on the left and right lower sides of 7a.
a, 24b are provided, and these pistons 24a,
By lifting one of the pinion gears 24b with compressed air, the frame plates 17a, 17b are swung upward to the right or upward to the left, one of the pinion gears 20a, 20b is engaged with the rack rod 10, and the other is separated from the rack rod 10. is configured to do so.

In addition, 25a and 25b in the figure adjust the retirement limit of the piston 24a or 24b that is being retired, and the rack 10a and pinion gear 20a or 20b are connected to each other.
A stopper 26 is a cover that covers the protruding end of the rack rod 10 for adjusting the occlusal state.

In the above configuration, if one of the one-way clutches 21a is configured to transmit the counterclockwise rotation of the rotating shaft 19a to the transmission gear 22a, and the other one-way clutch 21b is configured to have the opposite characteristics,
In the state shown in FIG. 2, the output shaft 16 is rotated clockwise via the pinion gear 20a, one-way clutch 21a, transmission gear 22a, and gear 23 only when the rack rod 10 moves to the right.
Moreover, if the pressure oil supply to the pistons 25a, 25b is reversed, the frame plates 17a, 17b are switched to the opposite position and swung, and only the other pinion gear 20b is engaged with the rack 10b, in this case, the rack rod 1
The output shaft 16 is driven and rotated counterclockwise only when 0 moves to the left.

That is, by selecting the pinion gears 20a, 20b that engage with the rack 10a, the rotation direction of the output shaft 16 can be switched between normal and reverse directions.

FIG. 3 shows an example of means for starting/stopping the air motor and switching between forward and reverse rotations.

Reference numeral 26 in the figure is a compressed air source such as a compressor, 27 is a relief valve for stabilizing air pressure, and 28
29 is a solenoid valve for starting the linear reciprocating mechanism 1, 29 is a solenoid valve for piston selection drive, and 30 is a motor starting/driving valve.
3 position switch for stopping and forward/reverse switching,
Ry ₁ is a relay for forward rotation drive, Ry ₂ is a relay for reverse rotation drive,
r ₁ and r ₂ are normally open relay contacts of relays Ry ₁ and Ry _2, respectively, and when the switch 30 is switched to the forward rotation contact as shown in the figure, compressed air is supplied to the linear reciprocating mechanism 1 via the solenoid valve 28. At the same time, compressed air supplied via the solenoid valve 29 causes the piston 2 to
5b is driven to protrude, and when the switch 30 is switched to the reversing contact, the solenoid valve 28 is similarly energized, and the solenoid valve 29 is switched to the reverse position, causing the piston 24a to be driven to protrude.
0 is returned to neutral, the solenoid valve 28 is returned to stop supplying compressed air to the linear reciprocating mechanism 1, and the solenoid valve 29 is also returned to neutral.

FIG. 4 shows a case where the air motor of the present invention is used to drive a roller conveyor 31 for conveying molds of a press machine, and the air motor is attached to a conveyor frame 32 through the case 13 of the rotation conversion mechanism 2. A driving shaft 35 and a motor output shaft 16 are fixed by bolts 33 and linked to each roller 34 by a chain, and are connected by inserting a key.

Next, some other embodiments of the present invention will be shown below.

(1) See Fig. 5 In this example, a pair of frame plates 17a and 17b that are rotatable around the axis of the output shaft 16 are swung to switch between forward and reverse directions, using a spring 36 in one direction (e.g. A case is shown in which one piston 24 biased toward the reverse drive side) is used, and the other configurations are the same as the main embodiment. This configuration simplifies the piston drive circuit for switching between forward and reverse directions.

(2) No illustrations The piston 7 of the linear reciprocating motion mechanism 1 may be driven in one direction by compressed air and moved in the opposite direction by a spring return movement. According to the small air motor according to the present invention, the following effects can be obtained.

By providing the frame plate, the first and second rotational transmission mechanisms, and the position switching means, the frame plate can be selectively switched between a forward rotation position and a reverse rotation position to drive the output shaft in forward rotation and reverse rotation. This makes it possible to significantly improve the practicality and versatility of the air motor. Moreover, the configuration for this purpose may be small and simple.

Since the frame plate, the first and second rotational transmission mechanisms, etc. can be arranged compactly within the case member, and the linear reciprocating mechanism is also attached to the case member, it is possible to obtain a small air motor that is compact as a whole.

[Brief explanation of drawings]

The drawings show an embodiment of a small air motor according to the present invention, and FIG. 1 is an overall plan view crossing the main parts;
Figure 2 is a longitudinal front view, Figure 3 is a configuration diagram showing the basic structure of the entire air motor and its operating means, and Figure 4 is a configuration diagram showing the basic structure of the entire air motor and its operating means.
The figure is a partially cutaway plan view showing an example of usage.
The figure is a longitudinal sectional front view of a main part showing an embodiment of the forward/reverse switching means. 1... linear reciprocating mechanism, 10... easy rod,
16... Output shaft, 20 (20a, 20b)... Pinion gear, 21 (21a, 21b)... One-way clutch.

Claims (1)

[Claims] 1. A case member; a rack rod that is supported movably in the axial direction by the case member and has a rack formed over a predetermined length range on one side; a linear reciprocating mechanism that reciprocates the rack rod by a predetermined stroke in the axial direction when supplied with the power; a shaft, a frame plate rotatably supported by the case member around the axis of the output shaft, and a first frame plate pivotally connected to the frame plate and capable of easy engagement.
a first rotation transmission mechanism having a pinion gear and interlockingly connecting the first pinion gear to the output shaft via a first one-way clutch; and a first rotation transmission mechanism that is pivotally connected to the frame plate on the opposite side of the output shaft from the first pinion gear and can be easily engaged with the first pinion gear. a second rotation transmission mechanism having a second pinion gear, the second pinion gear being interlocked and connected to the output shaft via the second one-way clutch whose rotational transmission direction is opposite to that of the first one-way clutch; a forward rotation position where the gear meshes and the second pinion gear does not mesh easily;
A small air motor characterized in that it is equipped with a position switching means for switching the rotational position of a frame plate between a reverse position where the second pinion gear is easily engaged and the first pinion gear is not easily engaged.