GB2229316A - Switches - Google Patents

Abstract

A switch comprises a first movable slider 8a carrying a contact 9a, a second slider 8b carrying a contact 9b and movable independently of the first slider 8a and a driving member 10 for moving a selected one of the sliders 8a, 8b. A stop 16 is selectively engageable with either one of the sliders 8a, 8b to prevent it moving when the driving member 10 is moved against the action of a spring by an operating member. A movable contact 11 is carried by the driving member 10. <IMAGE>

Description

SWITCH This invention relates to a switch which is used, for example, for turning on or off a power source or switching the polarity.

A conventional switch for switching, for example, the rotation of a motor normally or reversely is provided with a circuit of the type shown in Fig 7. Specifically, the conventional switch is constructed such that movable members la and ib, which are moved in a seesaw manner, are placed on supporting members 2a and 2b and the movable members la and ib simultaneously operated by a common operating member.

Accordingly, when the operating member is pressed on either one of the movable members la and Ib, the pressed movable member la or Ib is contacted with a stationary contact point 3a or 3b, whereas when the operating member impressed on the other, the other movable member la or lb is contacted with the other stationary contact point 4a or 4b.Since the stationary contact points 3a and 4b and the stationary contact points 3b and 4a are connected by lead wires 5 and 6, when the movable member la or ib is contacted with the right stationary contact point 3a or 3b as shown in the figure, an electric power is supplied to a motor M via the positive electrode of a power source E, the stationary contact point 3a, the movable member la, the motor M, the supporting member 2b, the movable member ib, the stationary contact point 3b, an on/off switch 7 and the negative electrode of the power source E, and as a result, the motor M is rotated normally.

On the contrary, when the common operating member is operated such that the movable member la or ib is contacted with the left stationary contact point 4a and 4b, an electric power is supplied to the motor M via the positive electrode of the power source E, the stationary contact point 3a, the lead wire 5, the stationary contact point 4b, the movable member ib, the motor M, the supporting member 2a, the movable member la, the stationary contact point 4a, the lead wire 6, the stationary contact point 3b, the on/off switch 7 and the negative electrode of the power source E, and as a result, the motor M is rotated reversely.

The conventional switch, however, has problems in that since the number of component parts is increased and grounding space is increased since the stationary contact points 3a and 4b, and the stationary contact points 3b and 4a must be connected by the lead wires 5 and 6 in "X" shape, and particularly, since a power switch 7 is required besides a switch for switching the polarity.

These problems occur because the two movable members la and ib are deigned such that they are moved together in the same direction. Further, in the case where there is provided a speed control circuit and a power source is directly connected after the speed is controlled, there requires a still additional switch, which results in an increase of the switches in number and inconvenience in operation.

The present invention has been accomplished in order to overcome the above-mentioned problems involved in the conventional switch.

It is therefore a general object of the present invention to provide a switch, in which two movable members la and ib are independently movable, so that a single switch is able to function as a switch for switching the polarity and as a switch for turning on or off a power source.

According to the present invention there is provided a switch comprising a first member which is movable between first and second positions thereby to perform a first switching operation, a second member which is movable, independently of said first member, between third and fourth positions thereby to perform a second switching operation, and a driving member which is operable to move one of said two movable members. The switch preferably includes at least two sliders and a driving member reciprocally movable by operation from outside to drive at least one of said two sliders, in which one of said two sliders is disposed to each side of the driving member. At least the two sliders are provided with a movable contact piece for switching respectively. The driving member may be provided with a movable member.One ends of the sliders are provided with a selection stopper, respectively, for independently regulating a selected stroke thereof. That is, the strokes of the two sliders can be selectively regulated depending on the position of the selection stopper.

When the driving member 10 is moved against the coil springs 15a and 15b interposed between the driving member 10 and and the sliders 8a and 8b, the sliders 8a and 8b are moved, and, as a result, the movable contact pieces 9a and 9b are slid to perform the switching action.

At that time, when the selection stopper 16 is pivotally moved to, for example, the chain line position shown by a, the slider 8b becomes unable to move, and the switching is performed only by the reciprocal movement of the movable contact piece 9a of the other slider 8a. On the contrary, when the selection stopper 16 is moved to, for example, the broken line position shown by b, the slider 8a becomes unable to move, and the switching is performed only by the reciprocal movement of the movable contact piece 9b of the other slider 8b.

And, when the driving member 10 provided with the movable contact piece 11 is further moved against the coil springs 15a and 15b, the switching is performed also by the movable contact piece 11 of the driving member 10. This switching action can be delayed for a certain time with respect to the switching action of the slider 8a and 8b. Otherwise, the switching action may be performed simulataneously with the switching action by the movable contact pieces 9a and 9b.

The above and other objects and attendant advantages of the present invention will be apparent to those skilled in the art from a reading of the following description and claims in conjunction with the accompanying drawings in which: Fig 1 is a perspective view showing an important portion of a switch according to the present invention; Fig 2 is an illustration showing the switching action; Fig 3 is an illustration showing one example of a circuit diagram; Figs 4 and 5 are sectional views showing the whole picture of one embodiment; Fig 6 is an exploded perspective view of a switch according to the embodiment; and Fig 7 is an illustration showing a positive switching circuit in which the conventional switch is employed.

One embodiment of a switch according to the present invention will be described with reference to the accompanying drawings.

Fig 1 is a perspective view showing an important portion ofa switch to the present invention. Figs 2(a) through 2(1) are illustrations showing the action of a switch according to the present invention, wherein the upper illustrations show the moving state of the contact points, the intermediate illustrations show the moving state of the sliders, and the bottom illustrations show the positions of the stopper.

In Fig 1, 8a and 8b denote sliders having movable contact pieces 9a and 9b. The sliders Ba and 8b are provided with a driving member 10 placed thereon. The driving member 10 is able to move in parallel relation with the sliders 8a and 8b and has a movable contact piece 11.

Either one of the sliders 8a and 8b has driving member carriers 12a and 12b for positioning the driving member 10, whereas the other slider 8a or 8b has spring carriers 13a and 13b. Between the spring carriers 14a and 14b of the driving member 10 and the spring bearings 13a and 13b of the sliders, compression coil springs 15a and 15b are interposed.

16 denotes a selection stopper able to select a neutral position shown by the solid line n, an a-position shown by the chain line and a b-position shown by the broken line by an external operation.

The operation of the switch will now be described. Suppose that the selection stopper 16 is in the a-position as shown by the chain line a. The driving member 10 is normally moved in the direction as shown by an arrow 17 by a spring, etc. In this position, when the driving member 10 is pressurized in the direction as shown by an arrow 18 against the arrow 17, the sliders 8a and 8b are pressurized toward the selection stopper 16 through the compression coil springs 15a and 15b. However, since the selection stopper 16 is in the a-position for preventing the movement of the left-hand side slider 8b, only the right-hand slider 8a is moved without being prevented by the selection stopper 16.When the driving member 10 is further moved in the direction shown by the arrow 18, only the driving member 10 is further moved against the compression coil spring 15a.

In this way, due to the movement of one slider 8a, the switching action is performed by the movable contact piece 9a and then the driving member 10 is moved. Therefore, the switching is somewhat delayingly performed by the movable contact piece 11.

When the driving member 10 is returned to the direction as shown by the arrow 17, the switching is performed first by the movable contact piece 11, then by the movable contact piece 9a and returned to its original state.

When the driving member 10 is moved in the direction as shown by the arrow 18 in the manner as previously described with the selection stopper 16 moved in the b-position as shown by the broken line, the slider 8a becomes unable to move prevented by the selection stopper 16. In the meantime, the other slider 8b is moved, the switching is performed by the movable contact piece 9b and the driving member 10 is further moved delayingly.

As a result, the switching is performed by the movable contact piece 11.

The driving member 10 is moved in the direction as shown by the arrow 18 with the selection stopper 16 moved in the neutral position shown by the solid line n. However, even if pressurized in the direction as shown by the arrow 18, since both sliders 8a and 8b are abutted against the selection stopper 16, the switching action is not taken place.

Fig 2 illustrates the various states of the above-mentioned actions. Figs 2(a) through 2(c) illustrate the states where the driving member 10 is restored to the direction as shown by the arrow 17. In those states, the movable contact piece 9a connects the stationary contact points 19a-20a, whereas the movable contact piece 9b connects the stationary contact points 19b-20b.

The movable contact piece 11 of the driving member 10 is situated on a common contact point 21.

Then, as shown in Figs 2(d) through 2(f), the selection stopper 16 is pivoted toward the slider 8b so as to permit the slider 8a to move. In that state, when the driving member 10 is moved in the direction as shown by the arrow 18, since only the slider 8a is moved toward the selection stopper 16 through the coil spring 15a as shown in Fig 2(e), the movable contact piece 9a is moved toward the common contact point 21 to connect the stationary contact point 19a with the common contact point 21.

When the driving member 10 is further moved as shown in Figs 2(g) through 2(i), the movable contact piece 11 connects the power source stationary contact point 22 with the common contact point 21 to turn the power source on.

When the driving member 10 is restored to its original state, the movable contact piece 11 is separated from the power source stationary contact point 22 and brought to the states as shown in Figs 2(d) through 2(f), and then the movable contact piece 9a is separated from the common contact point and returned to the contact point position as shown in Fig 2(a).

Next, as shown in Figs 2(j) through 2(1), when the driving member 10 is moved in the direction as shown by the arrow 18 with the selection stopper 16 pivoted toward the slider 8a for allowing the slider 8b to move, only the slider 8b is moved toward the selection stopper 16 through the coil spring 15 as shown in Fig 2(k). As a result, the movable contact piece 9b is moved toward the common contact point 21 to connect the stationary contact point 19b with the common contact point 21.

When the driving member 10 is further moved as in the cases of Figs 2(g) through 2(i), the movable contact piece 11 connects the power source stationary contact point 22 with the common contact point 22 to turn the power source on.

In this way, either by turning the selection stopper 16 to the position as shown in Fig 2(f) or to the position as shown in Fig 2(1), the movable contact pieces 9a and 9b can be selectively moved to be connected with the common contact point 21.

Fig 3 is an example in which a circuit for switching the rotating direction of a motor is constituted utilizing this switching mechanism. The stationary contact points 20a and 20b are connected with the positive electrode of the power source E, whereas the stationary contact points 19a and 19b are connected with both electrodes of the motor M. The common contact point 21 is connected with a speed control circuit 23, whereas the stationary contact point 22 is connected with the negative electrodes of the speed control circuit 23 and the power source E.

As shown by the solid line, the movable contact pieces 9a and 9b are in the stationary contact points 20a and 20b, respectively, and as shown in Fig 2(a), the stationary contact point 19a is connected with the stationary contact point 20a and the stationary contact point 19b is connected with the stationary contact point 20b to shorten the both electrodes of the motor M.

As a result, the motor M is unable to rotate, and the power source (the connection between the common contact point 21 and the stationary contact point 22) of the motor M is also in its off-state.

next, as shown in Fig 2(d), when the movable contact piece 9a is moved toward the contact point 21 to turn the connection therebetween, in Fig 3, the power source is supplied to the motor M via the positive electrode of the power source E, the stationary contact point 20b, the motor M, the stationary contact point 19a, the movable contact piece 9a, the common contact point 21, the rotation control circuit 23 and the negative electrode of the power source E, and as a result, the motor M starts a normal rotation, for example. As that time, the speed of rotation of the motor M becomes gradually fast due to the rotation speed control circuit 23.

Next, as shown in Fig 2(g), when the driving member 10 is further moved to connect the common contact point 21 with the stationary contact point 22 by the movable contact piece 11, the common contact point 21 is directly connected with the negative electrode of the power source E through the stationary contact point 22 and not via the speed control circuit 23 and rotated at a maximum speed.

As shown in Fig 2(j), when the movable contact piece 9b is moved toward the common contact point 21 to turn on the connection therebetween, in Fig 3, the power source is supplied to the motor M via the positive electrode, the stationary contact point 20b, 20q, the motor M, the stationary contact point l9b, the movable contact piece 9b, the common contact point 21, the speed control circuit 23, and the negative electrode of the power source E, and as a result, the motor M starts a reverse rotation and the rotation thereof becomes gradually fast.

When the driving member 10 is further moved to connect the common contact point 21 with the stationary contact point 22 by the movable contact piece 11, the common contact point 21 is directly connected with the negative electrode of the power source E'through the stationary contact point 22 and not via the speed control circuit 23 rotated at a maximum speed.

In this way, by selecting the position of the selection stopper 16, the sliders 8a and 8b are selectively moved, and by moving only one movable contact piece 9a or 9b, the switching of the electrode of the motor M can be performed. And, during the further movement of the driving member 10, there is provided a delayed time. During the time, the motor M is caused to rotated fast by the speed control circuit 23, and thereafter, the movable contact piece 11 is turned on so as to supply the power source directly to the motor M, thereby to effectively control the speed of rotation of the motor M.

Figs 4 and 5 are illustrations showing an actual use of a switch acording to the present invention, wherein Fig 4 is a sectional view in the position of the slider 8a or 8b, and Fig 5 is a sectional view in the central position of the driving member 10. A case-like main body 24 contains therein the sliders 8a and 8b and the driving member 10 shown in Fig 1. The main body 24 is provided with a handle 25 integral with the selection stopper 16 and projecting outward therefrom. Between the handle 25 and the main body 24, a moderating mechanism comprising a compression coil spring and a ball 26 is disposed so as to lock the selection stopper 16 in each position of n, a and b.

The handle portion 27 integral with the main body 24 contains therein a lever 28 swingably supported by a support shaft 29. One end of the lever 28 is engaged with the driving member 10, whereas the other end is projected outward from the handle 27 by a compression coil spring 30. When a trigger 31 is swingably supported with respect to the main body 24 is triggered, the lever 28 is swung counterclockwise against the compression coil spring 30, the driving member 10 is driven in the direction as shown by the arrow 18, and as a result, the switching is performed as described with reference to Figs 1 and 2.

Fig 6 is a perspective view showing various parts by exploding the switch of Figs 4 and 5. The case-like main body 24 contains therein the common contact point 21, the stationary contact points 19a, 19b, 20a and 20b, and the common contact point 22, and with the sliders 8a and 8b and the driving members 10 placed thereon, the compression coil spring 15a is inserted between the driving member carrier 12a and the spring carrier 13a and the compression coil spring 15b is inserted between the driving member carrier 12b and the spring carrier 13b. And, with a slide piece 32 of a slide resistor placed on the driving member 10 and with the coil spring and ball 26 for the moderating mechanism inserted into the selection stopper 16, a cover 33 is put thereon and secured thereto.

Further, with a restoring spring 30 and the lever 28 contained in the handle 27 and with the upper end of the lever 28 engaged with the driving member 10, the support shaft 29 is thrusted therethrough. The support shafts 35a and 35b of the main body 24 is fitted into the support holes 34a and 34b formed in the upper end of the trigger 31.

In this embodiment, in order to move the driving member 10 reciprocally, the swinging force of the lever 28 operated by the trigger 31 is utilized. However, the driving member 10 may be driven by means of a push button or a slide switch.

The selection stopper 16 employed in the embodiment is also only one example. Therefore, any other suitable mechanism may be employed as long as it can selectively regulate the moving range of the sliders 8a and 8b.

As described in the foregoing, according to the present invention, since the electrode can be switched by reciprocally moving the sliders 8a and 8b for switching the contact points independently and selectively, a single switch can be also equipped with the switch function for turning on or off the power source. Accordingly, it exhibits a significant technical effect in the respect that the number of parts can be reduced and the switch can be made small. Moreover, since the power source is directly connected after the speed control circuit is turned on by the movable contact pieces 9a and 9b of the sliders 8a and 8b and delayingly the common contact point 21 is closed, it proves to be very effective in an apparatus in which a speed control is required, particularly in the respect that the number of switches can be reduced and the operating performance is greatly improved.

Although the present invention has been described in its preferred form with a certain degree of particularity, it is understood that the present disclosure of the preferred form has been made only by way of example and that numerous changes in the details of construction and arrangement of parts may be resorted to without departing from the spirit and the scope of the present invention as hereinafter claimed.

Claims (9)

1. A switch comprising a first member which is movable between first and second positions thereby to perform a first switching operation, a second member which is movable, independently of said first member, between third and fourth positions thereby to perform a second switching operation, and a driving member which is operable to move at least one of said two movable members.

2. A switch according to Claim 1, in which said first and second members each comprise a slider disposed to each side of the driving member.

3. A switch according to Claim 1 or Claim 2 in which there is provided a selection stopper which is selectively engageable with either or both of said two movable members at one end thereof.

4. A switch according to any of the preceding claims in which each of said first and second movable members includes a contact piece for effecting said first and second switching operations.

5. A switch according to any of the preceding claims in which said driving member is movable between fifth and sixth positions thereby to perform a third switching operation.

6. A switch according to Claim 5 in which the driving member includes a contact piece for effecting said third switching operation.

7. A switch according to any of the preceding claims in which a compression spring is disposed between said driving member and each of said first and second members.

8. A switch according to Claim 1 and substantially as herein described.

9. A switch substantially as herein described with reference to Figs 1 to 6 of the accompanying drawings.