JPH0145081B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an operating lever used for starting, stopping, etc. in a power device such as a machine tool or a cargo handling machine.

[Technical background of the invention and its problems]

As shown in Figure 1, in lathes,
An operating lever 13 is attached to the side surface of the carriage 12 in order to rotate the main shaft 11.

This operating lever 13 is connected to a starting shaft 15 attached to a head 14 via an appropriate transmission means (for example, a gear train), and by rotating the operating lever 13, the starting shaft 15 is rotated by a predetermined angle. I am learning to give. The starting shaft 15 is the bed 1
The collar 18 is rotatably supported by a bearing 16 provided on the side surface of the collar 4, and a collar 18 provided with a dog 17 is fitted to the end, as shown in FIG.

By manually operating the operating lever 13 in the direction of arrow A or B (see Fig. 2), the dog 17 operates the forward rotation instruction switch LsF or reverse rotation instruction switch LsR, and the drive motor (not shown) is activated. The main shaft can be rotated forward or reverse by switching the rotation direction.

In such a machine, the operating lever 13 is in the neutral position while the main shaft is stopped rotating, but if the operator's elbow or foot accidentally comes into contact with it or some kind of falling object collides with it, the operating lever 13 If the main shaft 11 moves, it is extremely dangerous because the main shaft 11 will start rotating at an unexpected time. Therefore, safety measures are required to prevent such accidents.

[Purpose of the invention]

The present invention has been made with these points in mind, and it is an object of the present invention to provide a control lever for a power plant that can be operated safely at all times without reducing operability.

[Summary of the invention]

The present invention is an operating lever for a power plant, which comprises a grip part held by an operator's hand, and an arm connecting the grip part and an operated part of the power plant,
It is characterized in that a detection part of a contact switch is attached to the grip part.

According to the present invention, the contact switch is activated when the operator grips the grip part, and the power device is driven on condition that the contact switch is activated, so that the power device is suddenly activated due to an accidental change in the operating lever. It is possible to prevent accidents such as starting.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to FIGS. 3 and 4.

The operating lever 23 includes a grip portion 24 that is gripped by an operator, and an arm 26 that connects the grip portion 24 to an operated portion of the power plant, such as a shaft 25 attached to the carriage 12. Grip part 24
consists of a spherical grip ball 27 made of an insulator, and a detection section 28 of a contact switch incorporated and held in the grip ball 27, and an electric wire 29 for signal transmission is connected to the detection section 28. There is. The detection unit 28 is made of a metal conductor. In addition, electric wire 29
is guided to the carriage 12 side through the inside of the arm 26, and is connected to the controller of the contact switch.

A contact switch operates by detecting an electrical change in an oscillator circuit caused by an object, especially a human's bare hand, touching a detection part (sensing part). It has the characteristic that it does not.

FIG. 4 shows an electric circuit including a contact switch used to rotate the spindle 11 of the lathe described above in the forward and reverse directions. A controller CNT of a contact switch is connected between the bus lines X and Y, and a detection section 28 of the contact switch is connected to one input terminal of the controller CNT. In addition, between the busbars X and Y, there is an electromagnetic switch for rotating the main shaft motor.
MgF and MgR are installed in parallel, and the normally open contacts LsF-a and LsR-a of the forward and reverse rotation instruction switches LsF and LsR are the normally open contacts of the contact switch controller CNT.
They are each connected in series to CNTa, and a holding circuit is formed. The two holding circuits are released by a normally closed contact LsBb of a stop switch that is activated when the brake pedal 19 shown in FIG. 1 is depressed.

Next, the operation of this embodiment having such a configuration will be explained.

When the operator grasps the grip part 24 of the operating lever 23 with his bare hand, the detection part 28 senses this and activates the controller CNT of the contact switch via the electric wire 29. Next, when the operating lever 23 is moved in the direction of arrow A (see FIG. 2) while gripping the grip portion 24, the dog 17 rotates via the starting shaft 15, and the forward rotation instruction switch LsF is activated. As a result, the main shaft motor forward rotation electromagnetic switch MgF is activated, a holding circuit is formed, and the main shaft 11 is continuously rotated in the forward direction.

When the brake pedal 19 is pressed, the contact LsBb of the stop switch is activated, and the electromagnetic switch MgF for forward rotation of the main shaft is activated.
At the same time as the holding circuit is released, the rotation of the main shaft 11 is stopped.

Furthermore, when reversing, when the operating lever 23 is moved in the direction of arrow B, the contact switch and reversal instruction switch LsR are activated, and the electromagnetic switch is activated.
MgR operates and the main shaft 11 rotates in the reverse direction.

In this way, according to this embodiment, even if the operating lever is moved due to an elbow or foot touching the operating lever or colliding with some kind of falling object while the spindle is stopped rotating,
In the former case, the clothing is insulating, and in the latter case, the falling part is in space, so the space is insulating, and in both cases, the contact switch does not operate. Therefore, even if the forward rotation/reverse rotation instruction switch operates, the main shaft motor electromagnetic switch does not operate, and the main shaft does not rotate.

As described above, according to this embodiment, it is possible to prevent an accident in which the stopped main shaft suddenly starts rotating due to inadvertent movement of the operating lever, and is extremely safe. Furthermore, it can be manufactured without changing the shape of the conventional operating lever, and can be immediately applied to an existing lathe. Furthermore, since the contact switch does not require any special operating displacement, its operability and workability are not reduced compared to conventional operating levers.

In this embodiment, the operating lever used in a lathe has been described, but the operating lever according to the present invention can be similarly used in any other power device (for example, a cargo handling machine) that starts driving with the operating lever. can. In addition, in this embodiment, the main shaft drive motor is operated by a forward/reverse instruction switch to operate an electromagnetic switch to perform forward/reverse rotation of the main shaft. The electromagnetic clutch installed in the drive system of the main shaft is operated by the forward/reverse instruction switch, and the main shaft is rotated in the forward or reverse direction.
It may also be reversed. Further, the shape of the gripping portion may be, for example, an ellipsoid or a rectangular parallelepiped, in addition to the spherical shape.

〔Effect of the invention〕

As explained above, according to the present invention, it is possible to start driving the power plant only after two operations are performed: the contact switch is actuated by the operator's grip on the operating lever, and the instruction switch is activated when the operating lever is tilted down. This makes it possible to prevent sudden start of driving. This allows the operational safety of the power plant to be significantly improved. Also,
There is no need to change the shape of a ready-made operating lever, and there is no reduction in operability or workability.

INDUSTRIAL APPLICATION This invention can aim at improving the safety of a machine by using it as an operating lever of industrial machines, such as a machine tool and a cargo handling machine.

[Brief explanation of drawings]

Fig. 1 is a front view showing an embodiment of a lathe with an operating lever attached, Fig. 2 is a partially enlarged sectional view of a bearing portion of the lathe, and Fig. 3 is a sectional view showing an embodiment of an operating lever according to the present invention. , FIG. 4 is an electrical circuit diagram of a lathe drive unit using an operating lever according to the present invention. 23... Operating lever, 24... Gripping portion, 26...
...Arm, 27...Grip ball, 28...Detection section of contact switch.

Claims (1)

[Scope of Claims] 1. An operating lever for a power device comprising a grip portion held by an operator's hand and an arm connecting the grip portion and an operated portion of the power device, wherein the grip portion is in contact with The detection part of the switch is installed,
An operating lever for a power plant, characterized in that a normally open contact actuated by the contact switch is connected in series to a drive circuit of the power plant. 2. The operation according to claim 1, characterized in that the gripping part is composed of a detection part of a contact switch made of a conductive material and a gripping ball made of an insulator that holds the detection part. lever.