RU2560913C1 - Ski wax selection device - Google Patents

Abstract

FIELD: instrumentation.

SUBSTANCE: proposed device comprises base, power supply, control unit, measuring unit including n simulation discs and assemblies of couplers and locks of simulation discs. Measuring unit comprises extra n angular acceleration transducers, step motor to drive n torque transmission assemblies. The latter are coupled by vertical displacement assemblies with n simulation discs and assemblies of couplers and locks of simulation discs. To ensure uniform pressure of simulation disc on snow and required moment of inertia, said coupling and locking assemblies are provided with weights.

EFFECT: higher accuracy, accelerated determination of wax sliding properties.

2 cl, 3 dwg

Description

The invention relates to accessories for skiing and can be used to determine the characteristics of various surfaces, for example, sliding skis, which can be applied to various lubricants (paraffins, ski ointment, etc.).

Known devices for the selection of ski ointment (USSR author's certificate No. 787051 of 10/25/1978 and No. 1595545 of 12/24/1986), in which the model of the ski is made in the form of replaceable imitation discs driven by a spiral spring. The disadvantages of such devices is the complexity of the measurement process, caused by the need to cock the spring. In addition, the influence of the spring does not allow to obtain comparable measurement results when conducting parallel measurements using multiple devices, which does not allow to reduce the time for determining the sliding characteristics of ski greases. Moreover, to ensure the docking of the simulation disk during its installation, it is necessary to manually rotate the simulation disk around its axis, which leads to inconvenience of use and leads to additional time costs.

As a prototype, a device for evaluating ski lubricant was described, described in US patent No. 2008163667 dated 02.15.2005, containing a ski model in the form of a disk with a flat working surface on which a layer of ski ointment is applied, cargo elements, a drive mechanism including an electric motor with a known dependence of the current strength on the moment on the motor shaft, a battery, an electric motor control unit, and means for measuring electrical parameters that make it possible to evaluate the friction coefficient of lubricants. Using this device does not allow to obtain measurement results suitable for comparison, while measuring several devices at the same time. The differences in the measurement results obtained from different devices are due to the fact that each electric motor has unique electrical and mechanical characteristics. The disadvantage is the lack of measurement accuracy due to the influence of parasitic friction moments in the nodes of the electric motor and a change in its characteristics with increasing temperature of the windings during operation, which, in turn, is due to the impossibility of manufacturing an electric motor with a sufficiently accurate dependence of the current strength on the torque on the shaft in the entire range operating temperatures and speeds of rotation of the shaft, as well as measurements at different speeds of rotation of the simulation disk, since the rotation speed Avis on the coefficient of imitation drive on snow friction.

The invention is aimed at solving technical problems of increasing the accuracy of measurements and reducing the time for determining the sliding characteristics of ski greases.

Improving the accuracy of measurements is achieved through the use of a stepper motor, which simultaneously accelerates the n-number of simulation disks to a given speed in a given number of steps using the n-number of torque transmission nodes that allow you to disconnect the simulation disks from a stepper motor. The measurement is carried out with inertial rotation of the simulation discs, with open torque transmission nodes (so that the torque from the shaft of the stepper motor is not transmitted to the simulation discs). Given the high accuracy of the initial speed of the simulation discs provided by the stepper motor, the results are highly accurate.

Reducing the time to determine the sliding characteristics of ski ointments is achieved by providing the possibility of conducting parallel measurements of the characteristics of several ski ointments using several simulation discs that are simultaneously installed on the device.

To achieve these technical results, a device for selecting a ski ointment is proposed, which contains a base, a power source, a control unit, a measuring unit, which includes the n-number of simulation discs and the docking and fixing units of the simulation disc. The measuring unit further comprises an n-number of angular acceleration sensors, a stepper motor that transmits rotation to an n-number of torque transmission nodes, which are connected via vertical movement nodes to an n-number of docking and fixing nodes of the simulation disk. To ensure uniform pressure of the simulation disk on the snow and the necessary moment of inertia, the docking and fixing units are equipped with cargo elements.

The design of the ski ointment selection device is shown in FIG. 1, 2, 3.

The figure 1 shows the operating position of the device for the selection of ski ointment (imitation discs relate to snow), the figure 2 - position for changing the simulation discs and transportation, figure 3 - measuring unit of the device for the selection of ski ointment.

A device for selecting a ski ointment comprises a base (1), a power source (2), a control unit (3), vertical guides (4) and a measuring unit (5). The measuring unit (5) contains a stepper motor (6), n-number of torque transmission units (7) associated with the axis of the electric motor due to gear or friction transmission (8), n-number of angular acceleration sensors (9), n-number nodes of vertical movement transmission (10), cargo elements (11), n-number of simulation discs (13) and docking and fixing nodes of the simulation disc (12).

The device operates as follows. The base (1) is mounted on snow. In the working position (Fig. 1), the measuring unit (5) is at a predetermined distance above the snow surface, while the vertical displacement transmission units (10) provide a tight pressing of the simulation disks (13) to the snow surface under the action of the mass of cargo elements (11), located on the docking and fixing unit (12). Vertical guides (4) allow you to lift the measuring unit (5) above the surface of the snow and rotate it to a position that provides easy access to the simulation discs (13) for the purpose of their quick replacement (Fig. 2).

A stepper motor (6) provides simultaneous acceleration of the leading parts of the torque transmission units (7) to a predetermined speed by means of a friction or gear transmission. The torque transmission unit (7) allows you to break the transmission of torque from the drive shaft of the stepper motor to the follower at the command of the control unit (3). The torque transmission unit is made in the form of a friction electromagnetic clutch.

When turning on the torque transmission units (7), the stepper motor (6) transfers the torque to the simulation discs (13) through the vertical movement transmission units (10) and untwists them to a predetermined speed.

The measurement of the coefficient of friction of the ointment occurs during inertial rotation of the simulation discs as follows. When turning off the torque transmission units (7), the simulation discs (13) continue to rotate by inertia with a deceleration, which depends on the moment of inertia of the load elements (11) and the friction force between the working surface of the simulation discs (13) and the snow surface. Since the load elements (11) are designed in such a way that the moment of inertia of all simulation discs (13) is the same, the slowdown of the simulation discs (13) will be proportional to the coefficient of friction between the working surface of the simulation discs (13) and the snow surface. The deceleration of the simulation discs (13) is measured by angular acceleration sensors (9) and transmitted for processing to the control unit (3). The most suitable ski ointment is selected according to the test results by comparing the values of the friction coefficients of the surfaces of the simulation discs with various ski ointments applied to them on snow.

Claims (2)

1. A device for selecting a ski ointment containing a base, a power source, a control unit, a measuring unit including a simulation disk and a docking and fixing unit for the simulation disk, characterized in that the measuring unit further comprises an n-number of angular acceleration sensors, a stepper motor transmitting rotation to an n-number of torque transmission nodes, which are connected by means of vertical movement nodes to an n-number of docking and fixing nodes of a simulation disk. 2. The device according to p. 1, characterized in that the nodes of the docking and fixing are supplied with cargo elements.

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