GB2087741A - Pneumatically operated toy drill - Google Patents

Abstract

A compressor driven drill, converts the alternating exhaust and intake strokes of an air supply into a rotary motion in one direction. A piston 30 drives reciprocally a pair of racks 32, 33 which are located on opposite sides of a drill shaft 34. They cooperate with respective pinions 37,38 which are journalled on the shaft 34 and which drive the shaft in one direction only by way of respective one-way clutches 40, 41. <IMAGE>

Description

SPECIFICATION Pneumatically operated toy drill The present invention relates to a pneumatically operated toy drill which is driven by compressed air.

The object of the invention is to provide a toy drill which employs a simply constructed air supply that exhausts and intakes the air alternatingly, in order to continuously rotate the drill by utilizing both the exhausted air and the intaken air.

For this purpose, according to this invention, a piston in the toy drill is reciprocably operated by the air exhausted and intaken by the air supply, and the reciprocal operation is transformed into a sustained rotary motion of the drill in one direction through a motion transforming mechanism consisting of a pair of racks, a pair of pinions and a pair of clutches.

The invention will be described further hereinbelow, by way of example only, with reference to an embodiment illustrated in conjunction with the accompanying drawings, in which: Figure lisa perspective view of a toy drill and compressor unit; Figure 2 is a perspective view of the compressor with a portion removed to show the cells; Figure 3 is a simplified side view showing the working details of the air supply compressor; Figure 4 is a perspective view of the drill broken away to show the drive mechanism, and Figure 5 is an exploded view of the drill with the casing omitted.

The pneumatically operated toy drill according to this invention consists of a compressor unit 1 for supplying the air and a drill unit 2 which are connected together through a flexible tube 3 which sends the air.

The unit 1 has a shape similar two a practical com pressorthat is used in the construction site, and has a hollow body 4 and wheels 5 attached to the lower portions of the body 4. The upper portion of the rear half of the body 4 serves as a cell box 6 having a cover 6a which can be freely opened and closed, and accommodates cells 7 as illustrated in Fig. 2.

A cylinder unit 8 is provided in the front portion of the body 4 in parallel with the cell box 6. The cylinder unit 8 consists of a transparent cylindrical cover 9 having a shape resembling cooling fins, and a cylinder 10 secured in the cover 9. The upper end of the cylinder 10 serves as an air supply port 10a of a small diameter which protrudes beyond the upper end of the cover 9, and an end of the abovementioned tube 3 is connected to the supply port 1 0a.

A piston 11 is fitted in the cylinder 10, and the lower end of a rod 11 a is coupled to a drive mechanism which is installed in the body 4. Namely, a motor 12 is disposed in the body 4 beneath the cell box 6. A pinion 13 fastened to the tip of the output shaft of the motor is in mesh with a gear 15 which is supported by a rotary shaft 14 that is laterally supported in parallel with the output shaft. A pinion 16 which is formed together with the gear 15 as a unitary structure is in mesh with a gear 18 which is supported by another rotary shaft 17 that is laterally supported in parallel with the rotary shaft 14.

The above-mentioned gear train inclusive of the pinion gear 13 constitutes a reduction mechanism which transmits the rotation to the rotary shaft 14 via a gear 20 at a predetermined reduction ratio. A cam plate 21 which also serves as a fly-wheel is fastened to an end of the rotary shaft 14 beneath the piston 11, and the lower end of the piston rod 11 a is coupled to a coupling member 22 which is protruded from a deflected position on the outer side of the cam plate 21. The upper end of the piston rod 1 lea is swingably coupled by a pin to the piston 11.

A lever 23 for operating the engine is attached to the side surface at the front portion of the body 4.

The lever 23 for operating the engine has a knob 23a at an upper end thereof. The lower end of the lever 23 is rotatably supported in a cylindrical swollen portion 4a which is protruded at the front end of the body 4, and has, on its side surface, a moving contact 24 as shown in Fig. 3. The moving contact 24 is formed nearly in the shape of a fan, and a portion thereof is connected to one electrode of a cell which is the power supply through a lead wire 25.

A fixed contact 26 is mounted on the side of the swollen portion 4a to oppose to the moving contact 24, and is connected to another electrode of the cell through a lead wire 26a. Therefore, when the lever 23 for operating the engine is turned by a predetermined angle so that the moving contact 24 is brought into contact with the fixed contact 26, a power-supply circuit for the motor 12 is closed.

Accordingly, the rotation which is reduced at a predetermined reduction ratio through the abovementioned geartrain is transmitted to the cam plate 21, the piston 11 is caused to move up and down via the rod 1 lea accompanying the rotation of the cam plate 21, the air in the cylinder 10 is expelled and is intaken, and the positive pressure and negative pressure are supplied to the drill unit 2 via the tube 3.

The drill unit 2 is constructed as shown in Figs. 4 and 5.

Namely, the drill unit 2 according to this embodiment consists of a hollow frame 28 and a grip 29 formed together with the frame 28 as a unitary structure. The grip 29 can be held by human hand or by the hand of a doll to simulate the civil engineering works or rock-drilling works. The grip 29 also serves as a cylinder and has at its lower end a nipple 29a to which will be connected another end of the tube 3.

A piston 30 is slidably fitted in the grip 29 which also serves as a cylinder, and a U-shaped operation frame 31 is fastened to the upper end of a rod 30a that is connected to the upper end of the piston 30.

Pieces 32 and 33 are erected from both ends of a base plate 31a of the operation frame 31, and racks 32a, 33a are engraved on the inner side of the erected pieces 32,33. The two erected pieces 32 and 33 are located at diagonal positions at the corners of the base plate 31a of operation frame 31, and pinions 37 and 38 supported by a rotary shaft 34 are brought into mesh with the racks 32a, 33a of the erected pieces 32,33.

The rotary shaft 34 is laterally supported in the frame 28 of the drill unit 2 to run in the back and forth directions at right angles with the piston rod 30a which is located on the lower side, and the tip of the rotary shaft 34 is protruded forward beyond the frame 28 and is supported by a bearing member 35.

A drill 36 is attached to the tip of the rotary shaft 34.

Pinions which come into mesh with the racks 32a, 33a are rotatably supported by the rotary shaft 34 in the frame 28, and clutches 40,41 are fastened to the rotary shaft 34 on the outer sides of the pinions 37, 38. Clutch teeth 37a, 38a, 40a and 41 a are formed on the side surfaces of pinions 37,38 and clutches 40, 41, so thatthey will engage with each other when they are rotated in one direction only. Here, a set of pinion 37 and clutch 40 and another set of pinion 38 and clutch 41 are so constructed that either one of them will come into mesh when it is turned in one direction and the other set will come into mesh when it is turned in the opposite direction.Further, a coil spring 39 is loaded between the pinion 37 and the pinion 38, so that clutch pawls 37a, 38a of the pinions 37 and 38 will engge with pawls, 40a, 41 a of the opposing clutches 40 and 41.

The operation of the thus constructed pneumatically operated toy drill will now be explained below.

If now the lever 23 for operating the engine is turned in a direction ON, the moving contact 24 comes into contact with the fixed contact 26, whereby the power-supply circuit is closed and the motor 12 starts to run. The rotation of the motor 12 is transmitted to the cam plate 21 via the pinion 13 and reduction gear mechanism, and the piston 11 moves up and down via the rod 11 a.

As the piston 11 moves up and down, the air in the cylinder 10 is supplied into, or intaken from the grip 29 which also serves as the cylinder in the drill unit 2 via the tube 13. Therefore, the piston 30 moves up and down in the grip 29, and the racks 32a, 33a move up and down correspondingly. Referring to figure 4, racks 32a, 33a move upwards, the pinions 37,38 are rotated by a predetermined angle in the opposite directions relative to each other. In this case, the clutch pawl 37a of pinion 37 and the pawl 40a of clutch 40 of one side engage with each other to rotate the rotary shaft 34, i.e., to rotate the drill 36 in one direction, while the clutch pawl 38a of pinion 38 does not engage with the pawl 41 a of clutch 41 on the other side.When the racks 32a, 33a are lowered, on the other hand, the clutch pawl 37a of pinion 37 of one side does not engage with the pawl 40a of clutch 40, and the clutch pawl 38a of pinion 38 of the other side engages with the pawl 41 a of clutch 41 thereby to rotate the rotary shaft 34, i.e., to rotate the drill 36 in the same direction as mentioned above.

Accordingly, when the racks 32a, 33a move up and down repetitively accompanying the motion of the piston 30, the drill 36 continues to rotate in one direction.

According to this invention as mentioned in the foregoing, the positive pressure and the negative pressure produced by the intake operation and exhaust operation of the air supply are transmitted to the piston on the side of the drill, and the motion of the piston in the upper and lower directions is transformed into the rotary motion of drill or one direction via a pair of racks, a pair of pinions, and one-way clutches. Therefore, the toy drill of this invention is very interesting and offers the motion which resembles the motion of a practical drill.

Claims (5)

1. A pneumatically operated toy drill comprising a casing equipped with a cylinder connected to an air supply which exhausts and intakes the air alternatingly, a piston which is fitted in said cylinder and which performs the reciprocal operation being urged by the air intaken and exhausted by said air supply, a drill shaft which is rotatably supported in said casing and of which the tip is formed in the shape of a drill and is outwardly protruded, and a motion transforming mechanism which transforms the reciprocal motion of said piston into rotary motion of said drill, wherein said motion transforming mechanism consists of a pair of racks which are located on both sides of said drill shaft and which undergo the reciprocal motion together with said piston, a pair of pinions which rotate being in mesh with the racks, and a pair of clutches which transmit the rotation of the two pinions in one direction only to said drill shaft.

2. Atoy drill as claimed in claim 1, in which one clutch transmits rotation to the drill in the said direction during upward movement of the rack and the other clutch transmits rotation to the drill in the said direction during downward movement of the rack.

3. Atoy drill as claimed in claim 1 or 2, in which each clutch comprises co-operating teeth on an end face of the pinion and an adjoining shoulder of the shaft.

4. Atop drill as claimed in any of claims 1,2 or 3, in which the pinions are journalled for rotation on the shaft and are biased in a direction to load the clutches.

5. A pneumatically operated toy drill, constructed and arranged and adapted to operate substantially as hereinbefore described, with reference to and as illustrated in the accompanying drawings.