US2842000A - Speed governor device - Google Patents

Description

July 8, 1958 o. L. OTTOSSON 2,842,000

SPEED GOVERNOR DEVICE Filed Sept. 25, 1955 ll'l...

INVENTOR 0L 0F 1 opzwrz Orraaa a/v ATTORNEY United States Patent SPEED GOVERNOR DEVICE Olof Lorentz Ottosson, Motala, Sweden, assignor to Industriaktiebolaget Luxor, Motala, Sweden, a corporation of Sweden The present invention relates to a speed governor arranged between a driven member, e. g. the turntable of a phonograph, and a driving member, which governor comprises a variable transmission device and a centrifugal device controlling this transmission device and operatively connected to the driving member.

It is known to equalize the speed from a driving member with varying speed by means of a combination of a centrifugal device and a transmission device. In the British patent specification No. 328,737 a device is described, in which the regulation is effected by displacing a driving roller in relation to a driven disc, so that the radius from the engagement point of the driving roller on the driven disc to the shaft of the latter is changed when the speed of the driving member varies.

However, with this device a sufficiently constant speed cannot be obtained and therefore in practice it must be completed with an auxiliary governor of the type generally used, which also is indicated in the specification mentioned.

It is an object of the present invention to produce a speed governor by which the condition for a constant speed is fulfilled within a sufiiciently great range without using any auxiliary governor.

The invention will hereinafter be described with reference to the accompanying drawing.

Figs. 1 and 2 show a device according to the invention in two working positions.

Fig. 3 shows a diagram for determining the profile for a detail included in the device.

Figs. 1 and 2 show a device according to the invention, where the condition for having a constant speed is fulfilled within a sutficiently great range.

In the drawing 1 designates the driving member, from which the effect is transferred through the extended shaft 2. On this shaft a centrifugal device consisting of weights 3 fixed on levers 4 is arranged, which levers are fixed to a conical body 5, arranged on the shaft 2 and dis placeable along the length axis of this shaft, so that the levers are movable about their fixing points in a plane which contains the centre line of the shaft and the centre of gravity of the weights. Through the arms 6 fixed to the levers 4 through the joints 7 these levers are hinged to a disc 8, which is fixed to the shaft 2.

When the device rotates, the weights 3 are swung outwards from the shaft thereby pulling the conical body toward the driving member. The position of the conical body on the shaft is determined by the speed of the member mentioned, and the centrifugal force is balanced by the tension of the helical spring 9, which tends to press the body 5 away from the driving member.

A circular disc 10, the periphery of which is supplied with rubber or another material with a great coefficient of friction, is in engagement with the body 5. The revolution of the body 5 is also transferred to the disc 10, from where it may be transferred either through the shaft 11 or from its periphery e. g. to the turntable of a phonograph.

At rest the details of the device have the mutual positions shown in Fig. 1.

These positions are held, if the device is brought to rotate, until the speed is increased to a value No, at which the centrifugal forces on the weights 3 are as great as the components of the bias of the spring 9, transferred through the lever system 4, 6 and 7. This is the lower limit for the range of regulation of the governor. Thereby the disc 10 engages the envelope surface of the conical body 5 at a point, where the radius of the body is ro (Fig. 3).

If the speed is further increased, e. g. to Nx (Fig. 3), the weights 3 will be swung outwards from the shaft to a position of equilibrium, determined by the now existing new values of the centrifugal forces and the spring pressure. Hereby the body 5 has been displaced a distance x from the zero position, so that the disc 10 now engages the envelope surface of the body 5 at a point, where the radius is rx.

Evidently the condition for having a constant speed on the disc 10 from the lower speed limit of the driving member and upwards is that the body 5 has such a shape that the equality of rx-Nx=r0-No=constant is satisfied for every speed of the driving member within the range of regulation of the governor.

Every rotational speed within the of the centrifugal device corresponds to a given position of the body 5. The regulation characteristic of the centrifugal device is also a continuous connection between Nx and x, i. c. Nx=F (x).

If this function is combined with the abovementioned condition rx-Nx=constant, the equality of rx-F(x)= constant will be obtained, and from this finally rx= constant:F(x), where the contact radius rx on the body 5 is expressed as a function of the position coordinate x and constitutes the condition, which must be fulfilled by the transmission device for having a constant speed.

With a transmission device, w -ch consists of a displaceable cone and a disc engaging the cone, this condition can be fulfilled without any difiiculty, thereby that the cone is given the shape of a rotational body, the generating line of which is constituted by the curve rx= constant:F(x).

The function Nx =F(x) for a given centrifugal device is simply determined by measuring the displacement x at different speeds Nx. By marking out the obtained values in a diagram (Fig. 3) with the x-values along the abscissa and constant: Nx along the ordinate the cone profile, which is required for having a constant speed from the device when Nx varies, is obtained.

The value of the constant factor depends on the speed desired on the driven member.

Naturally it is also possible to modify the embodiment described in such a way, that the circular disc 10 is operatively connected with the centrifugal device and is displaced by this device along its rotational axis in engagement with the envelope surface of the conical body 5. Thereby the rotational motion to the driven member is transferred either from the shaft of the body 5 or through the direct engagement of the body with the driven member in a determined point of the envelope surface of the body.

According to the invention it is also possible to have a constant speed in a device according to the British patent specification 328,737. This is obtained by inserting a correction member, e. g. a cam disc, between the centrifugal device and the driving disc. This cam disc has for purpose to stretch out the inclined regulation characteristic of the centrifugal device, which makes the auxiliary governor unnecessary. The shape of the cam disc is determined in the same way as the shape of the conical body 5.

range of regulation What I-claim is:

A driving member and a driven membena speed-governor and a variable reduction gear arranged between said driving member and said-driven member, said speed governor comprising an arbitrarily chosen-centrifugal device operatively connected to said drivirr'g rnemb'er and controlling saidvariable reduction gear said gear comprising a conical body and a circ'ular'disc in engagement with said conical body, the shape of said body being accommodated to the regulation characteristic of said centrifugal device, said conical body being operatively connected to saidcentrifugal device and being by this device displaced along its rotational axis in relation to the' circular disc, whereby'atthe speed variations of the driving member the product of the speed of saidla'st men 4. tioned member and the radius of said conical body in the engagement point of said circular disc" is constant, the rotary motion of said circular disc being transferred from said disc to said driven member.

References Citedin the file of this patent UNITED STATES PATENTS 1,027,640 Bradford May 28, 1912 1,276,798 Whiting Aug. 20, 1918 1,433,596 Binfield etal. Oct; 31, 1922 2,312,798 Carrington Mar; 2, 1943 2,603,977 Cain July 22, 1952 FOREIGN PATENTS 265,805 Great Britain; Feb. 17, 1927

Images